U.S. patent application number 11/472255 was filed with the patent office on 2006-10-26 for counter-stream-mode oscillating-flow heat transport apparatus.
Invention is credited to Yasumasa Hagiwara, Seiji Inoue, Kimio Kohara, Kenichi Nara, Shinichi Yatsuzuka.
Application Number | 20060237177 11/472255 |
Document ID | / |
Family ID | 31891902 |
Filed Date | 2006-10-26 |
United States Patent
Application |
20060237177 |
Kind Code |
A1 |
Nara; Kenichi ; et
al. |
October 26, 2006 |
Counter-stream-mode oscillating-flow heat transport apparatus
Abstract
A counter-stream-mode oscillating-flow heat transport apparatus
improves heat transport capability by imparting oscillatory
displacement to a fluid located near a heat-generating element such
that the fluid is directed toward the heat-generating element.
Turning portions of serpentine flow paths are disposed to face the
heat-generating element. The flow paths are stacked in multiple
layers in the direction from the heat-generating element to the
flow paths, and a plurality of flow paths are disposed adjacent to
the heat-generating element in the direction of fluid
oscillation.
Inventors: |
Nara; Kenichi; (Obu-city,
JP) ; Hagiwara; Yasumasa; (Kariya-city, JP) ;
Kohara; Kimio; (Nagoya-city, JP) ; Yatsuzuka;
Shinichi; (Chiryu-city, JP) ; Inoue; Seiji;
(Nukata-gun, JP) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Family ID: |
31891902 |
Appl. No.: |
11/472255 |
Filed: |
June 21, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10634341 |
Aug 5, 2003 |
|
|
|
11472255 |
Jun 21, 2006 |
|
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Current U.S.
Class: |
165/148 ;
257/E23.098 |
Current CPC
Class: |
F28F 2260/02 20130101;
H01L 2924/0002 20130101; F28D 2021/0029 20130101; H05K 7/20272
20130101; F28F 2250/08 20130101; H01L 23/473 20130101; H01L
2924/0002 20130101; F28F 13/10 20130101; F28F 3/12 20130101; H01L
2924/00 20130101 |
Class at
Publication: |
165/148 |
International
Class: |
F28D 1/00 20060101
F28D001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 7, 2002 |
JP |
2002-229993 |
Mar 13, 2003 |
JP |
2003-067928 |
Jun 12, 2003 |
JP |
2003-167657 |
Claims
1. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein a plurality of said flow paths are disposed
adjacent to a heat source in a direction of fluid oscillation.
2. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 1, wherein said flow paths are stacked
in multiple layers in a direction from said heat source toward said
flow paths.
3. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 1, wherein a portion, of members
constituting said flow paths, other than a bounding portion for
defining a boundary of said adjacent flow paths is formed of a soft
material.
4. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 1, wherein said flow paths are
constructed such that material plates are shaped by etching or
stamping and stacked in layers in a direction of their
thickness.
5. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 1, wherein said flow paths are
constructed by jointing a wavy material plate having holes formed
thereon and plate-shaped material plates together.
6. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 1, wherein a movable element to be
displaced by an electromagnetic force and a piston for creating
fluid oscillations are integrated into an oscillating device for
inducing fluid oscillations.
7. A cooling device for cooling a heat-generating element using the
counter-stream-mode oscillating-flow heat transport apparatus
according to claim 1, further comprising: a radiating fin for
enhancing heat exchange between the fluid in said flow paths and an
external fluid, wherein an inside region the radiating fin is in
communication with said flow paths.
8. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein a heat reservoir for accumulating heat is disposed
between a heat source and said flow path having a fluid therein for
absorbing heat from said heat source.
9. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 8, wherein said heat reservoir is
formed of a material having a specific heat greater than or equal
to that of a member constituting said flow paths.
10. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 8, wherein said heat reservoir is
constructed such that a portion of members constituting said flow
paths, the portion facing said heat source, is thicker in thickness
than a bounding portion for defining a boundary of said adjacent
flow paths.
11. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein said flow paths are formed of a plurality of flow
paths extending in multiple directions.
12. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein a plurality of said flow paths are disposed
adjacent to a heat source in a direction of fluid oscillation, and
oscillatory displacement is imparted to a fluid of the fluids in
said flow paths, the fluid being located near said heat source,
such that the fluid is directed toward said heat source.
13. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 12, wherein a bounding portion for
defining a boundary of at least said adjacent flow paths of said
flow paths is bent.
14. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 13, wherein a heat reservoir for
accumulating heat is disposed between said heat source and said
flow path having a fluid therein for absorbing heat from said heat
source.
15. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 13, wherein the plurality of the flow
paths disposed adjacent to the heat source in a direction of fluid
oscillation extend in multiple directions.
16. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 15, wherein a heat reservoir for
accumulating heat is disposed between said heat source and said
flow path having a fluid therein for absorbing heat from said heat
source, said flow paths are formed of a plurality of flow paths
extending in the multiple directions.
17. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 12, wherein a heat reservoir for
accumulating heat is disposed between said heat source and said
flow path having a fluid therein for absorbing heat from said heat
source.
18. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 12, wherein said flow paths are formed
of a plurality of flow paths extending in multiple directions.
19. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 12, wherein a heat reservoir for
accumulating heat is disposed between said heat source and said
flow path having a fluid therein for absorbing heat from said heat
source, said flow paths are formed of a plurality of flow paths
extending in multiple directions.
20. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein a heat reservoir for accumulating heat is disposed
between a heat source and said flow path having a fluid therein for
absorbing heat from said heat source, and oscillatory displacement
is imparted to a fluid of the fluids in said flow paths, the fluid
being located near said heat source, such that the fluid is
directed toward said heat source.
21. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 20, wherein a bounding portion for
defining a boundary of at least said adjacent flow paths of said
flow paths is bent.
22. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 21, wherein said flow paths are formed
of a plurality of flow paths extending in multiple directions.
23. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 20, wherein said flow paths are formed
of a plurality of flow paths extending in multiple directions.
24. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein said flow paths are formed of a plurality of flow
paths extending in multiple directions, and oscillatory
displacement is imparted to a fluid of the fluids in said flow
paths, the fluid being located near a heat source, such that the
fluid is directed toward said heat source.
25. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 24, wherein a bounding portion for
defining a boundary of at least said adjacent flow paths of said
flow paths is bent.
26. A counter-stream-mode oscillating-flow heat transport apparatus
for inducing oscillations of counterflow fluids in adjacent flow
paths to thereby exchange heat between said adjacent flow paths and
transport heat from a hot region to a cold region, wherein a
bounding portion for defining a boundary of at least said adjacent
flow paths of said flow paths is bent, and a plurality of said flow
paths are disposed adjacent to a heat source in a direction of
fluid oscillation.
27. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 26, wherein a heat reservoir for
accumulating heat is disposed between the heat source and said flow
path having a fluid therein for absorbing heat from said heat
source.
28. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 27, wherein said flow paths are formed
of a plurality of flow paths extending in multiple directions.
29. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 26, wherein said flow paths are formed
of a plurality of flow paths extending in multiple directions.
30. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 26, wherein the bounding portion for
defining the boundary of at least said adjacent flow paths of said
flow paths is bent in two dimensions.
31. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein a bounding portion for defining a boundary of at
least said adjacent flow paths of said flow paths is bent, and a
heat reservoir for accumulating heat is disposed between a heat
source and said flow path having a fluid therein for absorbing heat
from said heat source.
32. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 31, wherein said flow paths are formed
of a plurality of flow paths extending in multiple directions.
33. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 31, wherein the bounding portion for
defining the boundary of at least said adjacent flow paths of said
flow paths is bent in three dimensions.
34. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein a bounding portion for defining a boundary of at
least said adjacent flow paths of said flow paths is bent, and said
flow paths are formed of a plurality of flow paths extending in
multiple directions.
35. The counter-stream-mode oscillating-flow heat transport
apparatus according to claim 34, wherein the plurality of said flow
paths are disposed adjacent to a heat source in a direction of
fluid oscillation
36. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein a plurality of said flow paths are disposed
adjacent to a heat source in a direction of fluid oscillation, and
a heat reservoir for accumulating heat is disposed between said
heat source and said flow paths having a fluid therein for
absorbing heat from said heat source.
37. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein a plurality of said flow paths are disposed
adjacent to a heat source in a direction of fluid oscillation, and
said flow paths are formed of a plurality of flow paths extending
in multiple directions.
38. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein a heat reservoir for accumulating heat is disposed
between a heat source and said flow path having a fluid therein for
absorbing heat from said heat source, and said flow paths are
formed of a plurality of flow paths extending in multiple
directions.
39. A counter-stream-mode oscillating-flow heat transport apparatus
defining flow paths and inducing oscillations of counterflow fluids
in adjacent flow paths to thereby exchange heat between said
adjacent flow paths and transport heat from a hot region to a cold
region, wherein a plurality of said flow paths are stacked in
layers in a crossover direction relative to a plane in contact with
a heat source.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of U.S. patent
application Ser. No. 10/634,341 filed Aug. 5, 2003 which is based
upon, claims the benefit of priority of, and incorporates by
reference, the contents of Japanese Patent Applications No.
2002-229993 filed Aug. 7, 2002, No. 2003-67928 filed Mar. 13, 2003,
and No. 2003-167657 filed Jun. 12, 2003.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a counter-stream-mode
oscillating-flow heat transport apparatus which creates
oscillations of counterflow fluid mediums in adjacent flow paths
and microchannels to thereby exchange heat between the adjacent
flow paths and transport heat from a hot region to a cold region,
the apparatus being effectively applicable to a thermally
quasi-superconductive plate, a thermal switch, a thermal diode, and
so forth.
[0004] 2. Description of the Related Art
[0005] As can be found in the URL,
"http://www.iis.u-tokyo.ac.jp/topics/1nishio.html," dated May 31,
2002, the counter-stream-mode oscillating-flow heat transport
apparatus is based on a principle that employs no phase change. The
principle of transferring heat in the counter-stream-mode
oscillating-flow heat transport apparatus relies on the so-called
"enhanced heat diffusion effect" which is produced by oscillating
flows, as described in the aforementioned URL.
[0006] To describe the effect in more detail, suppose that a
liquid-filled conduit has a temperature distribution as shown in
FIG. 22. For simplicity, consider a rectangular wave oscillation in
which an oscillation of the liquid stays at point H for half a
cycle and is then immediately transferred to point L and stays
there for the other half cycle, and is then immediately transferred
back to point H.
[0007] Take a liquid portion, referred to as an element, at point C
in absence of oscillation. When this element is oscillated to move
to point H, the element accepts heat from the wall of the conduit
because the temperature at point H on the wall is higher than that
of the element. When the element is further oscillated to move to
point L, the element releases heat to the wall since the
temperature at point L on the wall is lower than that of the
element.
[0008] In other words, one oscillation causes heat to be
transferred from point H to point L, like a frog jumps from one
place to another. Such a jump would never occur in absence of an
oscillation. Furthermore, the heat transfer or "jump" occurs
simultaneously with the oscillation. Thus, the higher the frequency
of the oscillation, the larger the number of jumps per unit time
becomes, while the larger the amplitude, the greater the distance a
jump becomes. That is, the accompanying displacement of heat due to
the jump increases with an increase in amplitude and cyclical
action. However, an increase in amplitude and cyclical action for a
greater amount of heat displacement would cause an increase in the
flow path resistance the pump load for inducing oscillation in a
liquid.
[0009] To effectively release heat from a heat-generating element
having high heat fluxes, it is critical to provide an improved
coefficient of heat transfer with a heating medium (such as water
or air). The improvement in the heat transfer coefficient can be
achieved by allowing the heating medium to flow through a
microchannel (micro-machined) flow path.
[0010] Accordingly, the higher the frequency of the oscillation,
the larger the number of jumps per unit time becomes, and the
larger the amplitude, the greater the distance of a jump. Thus, the
accompanying displacement of heat provided by the jump increases
with an increase in amplitude and cycle (e.g., see Japanese Patent
Laid-Open Publication No. 2002-364991).
[0011] On the other hand, the counter-stream-mode oscillating-flow
heat transport apparatus induces oscillations in a fluid through a
serpentine flow path to thereby create oscillations of counterflow
fluids in adjacent flow paths, and thus the apparatus has to be
provided with serpentine flow paths. In this context, the inventors
devised the following two methods for manufacturing the serpentine
flow paths.
[0012] That is, as shown in FIG. 47, according to a first
manufacturing method, there is provided a multi-hole tube 41 having
a plurality of holes 46 formed to penetrate from one end to the
other end along the length of the tube. Plates 51 are also provided
which each have recesses 50 for allowing adjacent holes 46 to
communicate with each other and which are coupled to both ends of
the multi-hole tube 41.
[0013] On the other hand, as shown in FIG. 48, according to the
second manufacturing method, there is also provided a multi-hole
tube 41 having a plurality of holes 46 formed to penetrate from one
end to the other end along the length thereof. The multi-hole tube
41 is constructed such that bounding walls for defining a boundary
of adjacent holes 46 are alternately cut or formed in a similar
manner at both the longitudinal ends thereof so as to allow
adjacent holes 46 to communicate with each other inside the
multi-hole tube 41 at the longitudinal ends. The longitudinal ends
of the multi-hole tube 41 are each blocked with a strip plate
52.
[0014] However, the first manufacturing method requires the plates
51 having the recesses 50 provided at a plurality of portions
therein to be separately manufactured. The plates 51 having the
recesses 50 provided at a plurality of portions therein are
complicated in shape. This leads to an increase in manufacturing
costs of the counter-stream-mode oscillating-flow heat transport
apparatus.
[0015] The second manufacturing method requires an additional
process of alternately cutting the bounding walls at the
longitudinal ends thereof, or the like, after the multi-hole tube
41 has been fabricated. This also results in an increase in
manufacturing costs of the counter-stream-mode oscillating-flow
heat transport apparatus.
[0016] Like the condenser tube employed in a vehicular air
conditioner, the multi-hole tube has a plurality of holes 46 formed
to penetrate from one end to the other end along its length and can
be fabricated by an extrusion processor by a drawing process.
Although the microchannel has a high heat transfer coefficient, its
reduced flow path area leads to a high pressure loss. This raises a
problem that a high power pump is required for the heating medium
to circulate through the flow path. Furthermore, the microchannel
is typically fabricated by cutting or etching; however, these
methods lead to an increase in manufacturing costs for the
microchannel.
SUMMARY OF THE INVENTION
[0017] The present invention was developed in view of the
aforementioned problems. It is therefore a first object of the
invention to provide a new counter-stream-mode oscillating-flow
heat transport apparatus that improves heat transport capability
when compared with the prior art. A second object is to provide a
counter-stream-mode oscillating-flow heat transport apparatus that
is capable of being manufactured more efficiently and at a lower
cost than the prior art.
[0018] To achieve the aforementioned objects, according to a first
aspect of the present invention, a counter-stream-mode
oscillating-flow heat transport apparatus induces oscillations of
counterflow fluids in adjacent flow paths (3) to thereby exchange
heat between the adjacent flow paths (3) and transport heat from a
hot region to a cold region, that is, from a hot side of a device
to a cold side. The apparatus is characterized in that oscillatory
displacement is imparted to a fluid of the fluids in the flow paths
(3), the fluid being located near a heat source (5), such that the
fluid is directed toward the heat source (5).
[0019] This allows oscillations and turbulence to be induced in the
fluid at a portion in the flow paths (3) corresponding to the heat
source (5), thereby providing an increased coefficient of heat
transfer between the heat source (5) and the fluid by the turbulent
effect by which a cold fluid collides intermittently against the
portion corresponding to the heat source (5). In contrast to this,
the prior art counter-stream-mode oscillating-flow heat transport
apparatus does not provide oscillatory movements in a manner such
that the fluid would collide against the heat source (5) at the
portion of the flow paths corresponding to the heat-generating
element, thus essentially providing no turbulent effect and a lower
coefficient of heat transfer than this embodiment.
[0020] As described above, this aspect enables a larger amount of
heat to be collected from the heat source (5) in a short period of
time than the prior art counter-stream-mode oscillating-flow heat
transport apparatus. This aspect thus provides a new
counter-stream-mode oscillating-flow heat transport apparatus which
is different from the prior art and provides improved heat
transport capability when compared with the prior art
counter-stream-mode oscillating-flow heat transport apparatus.
[0021] The invention according to a second aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. This makes it possible to obtain a new
counter-stream-mode oscillating-flow heat transport apparatus that
is different from the prior art while preventing the
counter-stream-mode oscillating-flow heat transport apparatus from
being increased in size.
[0022] The invention according to a third aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a plurality of the flow paths
(3) are disposed adjacent to a heat source (5) in a direction of
fluid oscillation.
[0023] The fluid exchanges heat with the heat source (5) at a
portion of the flow paths (3) corresponding to the heat source (5)
in a manner such that the greater the difference in temperature
between the fluid and the heat source (5), the more the linear
increase in the quantity of heat exchange becomes. In contrast to
this, the quantity of heat exchange is not linearly increased as
the opposing area between the heat source (5) and the fluid
increases, but reaches a saturation point against the increase in
the opposing area.
[0024] That is a maximum temperature difference .DELTA.T is given
between the fluid and the heat source (5) at an end of the heat
source (5). However, since the quantity of heat exchange is reduced
exponentially in response to an increase in the opposing area
between the heat source (5) and the fluid, an increase in the
quantity of heat exchange through the opposing area between the
heat source (5) and the fluid will become saturated.
[0025] Here, the prior art counter-stream-mode oscillating-flow
heat transport apparatus employs one flow path (3) adjacent to the
heat source (5) in the direction of fluid oscillation, whereas the
counter-stream-mode oscillating-flow heat transport apparatus,
according to an aspect of the present invention, employs a
plurality of flow paths (3) adjacent to the heat source (5) in the
direction of fluid oscillation. Suppose that both the prior art
counter-stream-mode oscillating-flow heat transport apparatus and
the counter-stream-mode oscillating-flow heat transport apparatus
according to the present aspect have the same total opposing
area.
[0026] In this case, the counter-stream-mode oscillating-flow heat
transport apparatus according to an aspect of the present invention
has a smaller opposing area per one piece than the prior art
counter-stream-mode oscillating-flow heat transport apparatus.
However, as described above, the increase in the quantity of heat
exchange through the opposing area is saturated. Thus, even for a
reduced opposing area per one piece, the arrangement with a
plurality of flow paths (3) adjacent to the heat source (5) can
provide, as a whole, an increased quantity of heat to be absorbed
from the heat source (5). Accordingly, it is possible to obtain a
new counter-stream-mode oscillating-flow heat transport apparatus
which is different from the prior art and which ensures an improved
heat transport capability while preventing the counter-stream-mode
oscillating-flow heat transport apparatus from increasing in
size.
[0027] The invention according to a fourth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a heat reservoir (7) for
accumulating heat is disposed between a heat source (5) and the
flow path (3) having a fluid therein for absorbing heat from the
heat source (5).
[0028] To collect heat from the heat source (5) with a high degree
of efficiency, a large temperature difference .DELTA.T is required
between the heat source (5) and the fluid. However, oscillatory
displacements and turbulence in the fluid at a portion of the flow
paths (3) corresponding to the heat source (5) lead to a sudden
variation in the temperature difference .DELTA.T in a short period
of time. Therefore, a relatively low frequency of oscillation is
required of the fluid in order to prevent a sudden variation in the
temperature of the heat source (5) in a short period of time;
however, it is difficult for this means to ensure an improved heat
transport capability.
[0029] In contrast to this, the present aspect is provided with the
heat reservoir (7) between the heat source (5) and the flow path
(3) present in which is the fluid that absorbs heat from the heat
source (5). The heat reservoir (7) serves as a buffer for
accommodating changes in temperature although the heat transfer
from the heat source (5) to the fluid is retarded by the heat
reservoir (7), thereby making it possible to provide an increased
frequency of oscillation for the fluid.
[0030] Accordingly, since the frequency of oscillation of the fluid
can be increased, it is possible to increase the total quantity of
heat transport even when the heat transfer from the heat source (5)
to the fluid is retarded by the heat reservoir (7). It is also
possible to obtain a new counter-stream-mode oscillating-flow heat
transport apparatus which is different from the prior art and
increases the total quantity of heat transport while reducing
variations in temperature of the heat source (5).
[0031] The invention according to a fifth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that the flow paths (3) are formed of
a plurality of flow paths (3) extending in multiple directions.
[0032] This makes it possible to obtain a new counter-stream-mode
oscillating-flow heat transport apparatus which is different from
the prior art and which provides an increased area contributing to
heat exchange between adjacent flow paths (3) thereby ensuring an
improvement in the heat transport capability while preventing the
counter-stream-mode oscillating-flow heat transport apparatus from
increasing in size.
[0033] The invention according to a sixth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. Furthermore, oscillatory displacement is
imparted to a fluid of the fluids in the flow paths (3), the fluid
being located near a heat source (5), such that the fluid is
directed toward the heat source (5). More specifically, this aspect
is a combination of the first and second aspects.
[0034] The invention according to a seventh aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a plurality of the flow paths
(3) are disposed adjacent to a heat source (5) in a direction of
fluid oscillation and oscillatory displacement is imparted to a
fluid of the fluids in the flow paths (3). The fluid is located
near the heat source (5), such that the fluid is directed toward
the heat source (5). More specifically, this aspect is a
combination of the first and third aspects.
[0035] The invention according to an eighth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a heat reservoir (7) for
accumulating heat is disposed between a heat source (5) and the
flow path (3) having a fluid therein for absorbing heat from the
heat source (5). Oscillatory displacement is imparted to a fluid of
the fluids in the flow paths (3), the fluid being located near the
heat source (5), such that the fluid is directed toward the heat
source (5). More specifically, this invention is a combination of
the first and fourth aspects.
[0036] The invention according to a ninth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that the flow paths (3) are formed of
a plurality of flow paths (3) extending in multiple directions.
Oscillatory displacement is imparted to a fluid of the fluids in
the flow paths (3), the fluid being located near a heat source (5),
such that the fluid is directed toward the heat source (5). More
specifically, this aspect is a combination of the first and fifth
aspects.
[0037] The invention according to a tenth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. Furthermore, a plurality of the flow paths (3)
are disposed adjacent to a heat source (5) in a direction of fluid
oscillation. More specifically, this aspect is a combination of the
second and third aspects.
[0038] The invention according to an eleventh aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. Furthermore, a heat reservoir (7) for
accumulating heat is disposed between a heat source (5) and the
flow path (3) having a fluid therein for absorbing heat from the
heat source (5). More specifically, this invention is a combination
of the second and fourth aspects.
[0039] The invention according to a twelfth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. The flow paths (3) are formed of a plurality of
flow paths (3) extending in multiple directions. More specifically,
this invention is a combination of the second and fifth
aspects.
[0040] The invention according to a thirteenth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a plurality of the flow paths
(3) are disposed adjacent to a heat source (5) in a direction of
fluid oscillation. Furthermore, a heat reservoir (7) for
accumulating heat is disposed between the heat source (5) and the
flow path (3) having a fluid therein for absorbing heat from the
heat source (5). More specifically, this invention is a combination
of the third and fourth aspects.
[0041] The invention according to a fourteenth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a plurality of the flow paths
(3) are disposed adjacent to a heat source (5) in a direction of
fluid oscillation. Furthermore, the flow paths (3) are formed of a
plurality of flow paths (3) extending in multiple directions. More
specifically, this aspect is a combination of the third and fifth
aspects.
[0042] The invention according to a fifteenth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a heat reservoir (7) for
accumulating heat is disposed between a heat source (5) and the
flow path (3) having a fluid therein for absorbing heat from the
heat source (5), while the flow paths (3) are formed of a plurality
of flow paths (3) extending in multiple directions. More
specifically, this aspect is a combination of the fourth and fifth
aspects.
[0043] The invention according to a sixteenth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. Furthermore, a plurality of the flow paths (3)
are disposed adjacent to a heat source (5) in a direction of fluid
oscillation and oscillatory displacement is imparted to a fluid of
the fluids in the flow paths (3). The fluid is located near the
heat source (5) such that the fluid is directed toward the heat
source (5). More specifically, this aspect is a combination of the
first, second and third aspects.
[0044] The invention according to a seventeenth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. Moreover, a heat reservoir (7) for accumulating
heat is disposed between a heat source (5) and the flow path (3)
having a fluid therein for absorbing heat from the heat source (5).
Additionally, oscillatory displacement is imparted to a fluid of
the fluids in the flow paths (3), the fluid being located near the
heat source (5), such that the fluid is directed toward the heat
source (5). More specifically, this aspect is a combination of the
first, second and fourth aspects.
[0045] The invention according to an eighteenth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. Furthermore, the flow paths (3) are formed of a
plurality of flow paths (3) extending in multiple directions and
oscillatory displacement is imparted to a fluid of the fluids in
the flow paths (3). The fluid is located near a heat source (5),
such that the fluid is directed toward the heat source (5). More
specifically, this aspect is a combination of the first, second and
fifth aspects.
[0046] The invention according to a nineteenth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a plurality of the flow paths
(3) are disposed adjacent to a heat source (5) in a direction of
fluid oscillation. A heat reservoir (7) for accumulating heat is
disposed between the heat source (5) and the flow path (3) having a
fluid therein for absorbing heat from the heat source (5), and
oscillatory displacement is imparted to a fluid of the fluids in
the flow paths (3), the fluid being located near the heat source
(5) such that the fluid is directed toward the heat source (5).
More specifically, this aspect is a combination of first, third,
and fourth aspects.
[0047] The invention according to a twentieth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a plurality of the flow paths
(3) are disposed adjacent to a heat source (5) in a direction of
fluid oscillation. The flow paths (3) are formed of a plurality of
flow paths (3) extending in multiple directions, and oscillatory
displacement is imparted to a fluid of the fluids in the flow paths
(3), the fluid being located near the heat source (5), such that
the fluid is directed toward the heat source (5). More
specifically, this aspect is a combination of the first, third, and
fifth aspects.
[0048] The invention according to a twenty-first aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a heat reservoir (7) for
accumulating heat is disposed between a heat source (5) and the
flow path (3) having a fluid therein for absorbing heat from the
heat source (5). The flow paths (3) are formed of a plurality of
flow paths (3) extending in multiple directions, and oscillatory
displacement is imparted to a fluid of the fluids in the flow paths
(3), the fluid being located near the heat source (5), such that
the fluid is directed toward the heat source (5). More
specifically, this aspect is a combination of the first, fourth,
and fifth aspects.
[0049] The invention according to a twenty-second aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. A plurality of the flow paths (3) are disposed
adjacent to a heat source (5) in a direction of fluid oscillation,
and a heat reservoir (7) for accumulating heat is disposed between
the heat source (5) and the flow path (3) having a fluid therein
for absorbing heat from the heat source (5). More specifically,
this aspect is a combination of the second, third, and fourth
aspects.
[0050] The invention according to a twenty-third aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. A plurality of the flow paths (3) are disposed
adjacent to a heat source (5) in a direction of fluid oscillation,
and the flow paths (3) are formed of a plurality of flow paths (3)
extending in multiple directions. More specifically, this aspect is
a combination of the second, third, and fifth aspects.
[0051] The invention according to a twenty-fourth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. The flow paths (3) are formed of a plurality of
flow paths (3) extending in multiple directions, and a heat
reservoir (7) for accumulating heat is disposed between a heat
source (5) and the flow path (3) having a fluid therein for
absorbing heat from the heat source (5). More specifically, this
aspect is a combination of the second, fourth and fifth
aspects.
[0052] The invention according to the twenty-fifth aspect provides
a counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a plurality of the flow paths
(3) are disposed adjacent to a heat source (5) in a direction of
fluid oscillation. The flow paths (3) are formed of a plurality of
flow paths (3), extending in multiple directions, and a heat
reservoir (7) for accumulating heat is disposed between the heat
source (5) and the flow path (3) having a fluid therein for
absorbing heat from the heat source (5). More specifically, this
aspect is a combination of the third, fourth and fifth aspects.
[0053] The invention according to the twenty-sixth aspect provides
a counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. A plurality of the flow paths (3) are disposed
adjacent to a heat source (5) in a direction of fluid
oscillation.
[0054] A heat reservoir (7) for accumulating heat is disposed
between the heat source (5) and the flow path (3) having a fluid
therein for absorbing heat from the heat source (5), and
oscillatory displacement is imparted to a fluid of the fluids in
the flow paths (3), the fluid being located near the heat source
(5), such that the fluid is directed toward the heat source (5).
More specifically, this invention is a combination of the invention
according to the first, second, third and fourth aspects.
[0055] The invention according to the twenty-seventh aspect
provides a counter-stream-mode oscillating-flow heat transport
apparatus for inducing oscillations of counterflow fluids in
adjacent flow paths (3) to thereby exchange heat between the
adjacent flow paths (3) and transport heat from a hot region to a
cold region.
[0056] Furthermore, the apparatus of the twenty-seventh aspect is
characterized in that a bounding portion for defining a boundary of
at least the adjacent flow paths (3) of the flow paths (3) is bent.
A plurality of the flow paths (3) disposed adjacent to a heat
source (5) in a direction of fluid oscillation extends in multiple
directions, and oscillatory displacement is imparted to a fluid of
the fluids in the flow paths (3). The fluid is located near the
heat source (5), such that the fluid is directed toward the heat
source (5). More specifically, this aspect is a combination of the
first, second, third, and fifth aspects.
[0057] The invention according to a twenty-eighth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. A heat reservoir (7) for accumulating heat is
disposed between a heat source (5) and the flow path (3) having a
fluid therein for absorbing heat from the heat source (5). The flow
paths (3) are formed of a plurality of flow paths (3) extending in
multiple directions, and oscillatory displacement is imparted to a
fluid of the fluids in the flow paths (3). The fluid is located
near the heat source (5), such that the fluid is directed toward
the heat source (5). More specifically, this aspect is a
combination of the first, second, fourth, and fifth aspects.
[0058] The invention according to the twenty-ninth aspect provides
a counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a plurality of the flow paths
(3) are disposed adjacent to a heat source (5) in a direction of
fluid oscillation. A heat reservoir (7) for accumulating heat is
disposed between the heat source (5) and the flow path (3) having a
fluid therein for absorbing heat from the heat source (5). The flow
paths (3) are formed of a plurality of flow paths (3) extending in
multiple directions, and oscillatory displacement is imparted to a
fluid of the fluids in the flow paths (3). The fluid being located
near the heat source (5), such that the fluid is directed toward
the heat source (5). More specifically, this aspect is a
combination of the first, third, fourth, and fifth aspects.
[0059] The invention according to a thirtieth aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. A plurality of the flow paths (3) are disposed
adjacent to a heat source (5) in a direction of fluid oscillation.
A heat reservoir (7) for accumulating heat is disposed between the
heat source (5) and the flow path (3) having a fluid therein for
absorbing heat from the heat source (5), and the flow paths (3) are
formed of a plurality of flow paths (3) extending in multiple
directions. More specifically, this aspect is a combination of the
second, third, fourth, and fifth aspects.
[0060] The invention according to a thirty-first aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a bounding portion for defining
a boundary of at least the adjacent flow paths (3) of the flow
paths (3) is bent. A plurality of the flow paths (3) are disposed
adjacent to a heat source (5) in a direction of fluid oscillation.
A heat reservoir (7) for accumulating heat is disposed between the
heat source (5) and the flow path (3) having a fluid therein for
absorbing heat from the heat source (5). The flow paths (3) are
formed of a plurality of flow paths (3) extending in multiple
directions, and oscillatory displacement is imparted to a fluid of
the fluids in the flow paths (3), the fluid being located near the
heat source (5), such that the fluid is directed toward the heat
source (5). More specifically, this aspect is a combination of the
first, second, third, fourth, and fifth aspects.
[0061] The invention according to the thirty-second aspect is
characterized in that the bounding portion for defining the
boundary of at least the adjacent flow paths (3) of the flow paths
(3) is bent in two dimensions.
[0062] The invention according to the thirty-third aspect is
characterized in that the bounding portion for defining the
boundary of at least the adjacent flow paths (3) of the flow paths
(3) is bent in three dimensions.
[0063] The invention according to the thirty-fourth aspect is
characterized in that the heat reservoir (7) is formed of a
material having a specific heat greater than or equal to that of a
member constituting the flow paths (3).
[0064] The invention according to the thirty-fifth aspect is
characterized in that the heat reservoir (7) is constructed such
that a portion (3c) of members constituting the flow paths (3), the
portion (3c) facing the heat source (5), is thicker in thickness
than a bounding portion (3b) for defining a boundary of the
adjacent flow paths (3).
[0065] The invention according to the thirty-sixth aspect is
characterized in that the flow paths (3) are stacked in multiple
layers in a direction from the heat source (5) toward the flow
paths (3). This makes it possible to provide an increased area
contributing to heat exchange between adjacent flow paths (3)
thereby ensuring an improvement in the heat transport capability
while preventing the counter-stream-mode oscillating-flow heat
transport apparatus from being increased in size.
[0066] The invention according to the thirty-seventh aspect is
characterized in that a portion (3d) of members constituting the
flow paths (3), other than a bounding portion (3b) for defining a
boundary of the adjacent flow paths (3), is formed of a soft
material. This allows the counter-stream-mode oscillating-flow heat
transport apparatus to be readily bent just like an electric cord,
thereby facilitating the implementation of the counter-stream-mode
oscillating-flow heat transport apparatus.
[0067] The invention according to the thirty-eighth aspect is
characterized in that the flow paths (3) are constructed such that
material plates are shaped by etching or stamping and stacked in
layers in a direction of their thickness.
[0068] The invention according to the thirty-ninth aspect is
characterized in that the flow paths (3) are constructed by
jointing a wavy material plate (3h) having holes formed thereon and
plate-shaped material plates (3j) together.
[0069] The invention according to the fortieth aspect is
characterized in that a movable element to be displaced by an
electromagnetic force and a piston for creating fluid oscillations
are integrated into an oscillating device (6) for inducing fluid
oscillations.
[0070] The invention according to a forty-first aspect provides a
cooling device for cooling a heat-generating element using the
counter-stream-mode oscillating-flow heat transport apparatus
according to any one of the first to fortieth aspects. The cooling
device is characterized by having a radiating fin (4a) for
enhancing heat exchange between the fluid in the flow paths (3) and
an external fluid, and in that an inside of the radiation fin (4a)
is in communication with the flow paths (3). This makes it possible
to provide improved thermal dissipation capability and thus an
increased total quantity of heat transport.
[0071] The invention according to a forty-second aspect provides a
counter-stream-mode oscillating-flow heat transport apparatus for
inducing oscillations of counterflow fluids in adjacent flow paths
(3) to thereby exchange heat between the adjacent flow paths (3)
and transport heat from a hot region to a cold region. The
apparatus is characterized in that a plurality of the flow paths
(3) are stacked in layers in a crossover direction relative to a
plane in contact with a heat source (5).
[0072] The stack in multiple layers makes it possible to provide an
increased area contributing to heat exchange between adjacent flow
paths (3), thereby ensuring an improvement in the heat transport
capability, while preventing the counter-stream-mode
oscillating-flow heat transport apparatus from increasing in
size.
[0073] It is yet another object of the present invention to reduce
the pressure loss of a heating medium in a heat transport apparatus
having flow paths for the heating medium which are formed into
microchannels. It is also another object of the invention to reduce
the manufacturing cost of the heat transport apparatus
incorporating the microchannel.
[0074] To achieve the aforementioned objects, the invention
according to a forty-third aspect provides a heat transport
apparatus, comprising flow paths (103 to 183) for a fluid to flow
therethrough, for transporting heat generated by a heat source
(200) from a hot region to a cold region via the fluid. The
apparatus is characterized in that a microchannel is formed in the
flow paths in the vicinity of the heat source, where the flow paths
are reduced in size relative to other portions.
[0075] As described above, only part of the flow paths of the heat
transport apparatus is formed into microchannels, thereby making it
possible to reduce the manufacturing cost of the heat transport
apparatus. Additionally, upon forming part of the flow paths into
microchannels, flow paths disposed in the vicinity of a heat source
having high heat fluxes can be formed into microchannels, thereby
releasing heat effectively from the heat source. Since only part of
the flow paths is formed into microchannels, it is also possible to
prevent an increase in pressure loss and thereby save power of a
drive means for driving the fluid. The "vicinity of the heat
source" in which the flow paths are formed into microchannels means
a location and a portion having a size corresponding to the heat
source in the heat transport apparatus, also including those
locations and portions having sizes slightly larger or slightly
smaller than the heat source.
[0076] The invention according to a forty-fourth aspect has a
tube-shaped aluminum member having a plurality of through-holes
formed parallel to each other, the through-holes constituting the
flow paths. The use of such an inexpensive aluminum member makes it
possible to manufacture the heat transport members at a low
cost.
[0077] The invention according to a forty-fifth aspect is
characterized in that the microchannel is formed by applying an
external force to and thereby compressing the flow paths in the
vicinity of the heat source. This allows the microchannel to be
formed at a lower cost than by cutting or the like.
[0078] As set forth in the invention according to a forty-sixth
aspect, the microchannel can be formed of one or more tubular
members or one or more rod-like members disposed in the flow paths
in the vicinity of the heat source. On the other hand, as set forth
in the invention according to a forty-seventh aspect, the
microchannel can be formed of a metal with ends in cavity
communication with each other in a flow direction of the fluid, the
metal being disposed in the flow paths in the vicinity of the heat
source. This also allows the microchannel to be formed at lower
costs than by cutting or the like. Furthermore, as set forth in the
invention according to a forty-eighth aspect, the metal with the
cavity can be formed of a foamed metal, a sintered metal, or a
metal formed by thermal spraying.
[0079] The invention according to a forty-ninth aspect is
characterized in that the flow of the fluid is a reciprocating flow
with a predetermined cycle and a predetermined amplitude. The use
of such an oscillating flow makes it readily possible to make a
wide range of adjustments to the heat transport performance by
controlling the frequency and amplitude of the fluid.
[0080] The present invention according to a fiftieth aspect
provides a counter-stream-mode oscillating-flow heat transport
apparatus for inducing oscillations of counterflow fluids in
adjacent flow paths (60) to thereby exchange heat between the
adjacent flow paths (60) and transport heat from a hot side
(region) to a cold side (region). The apparatus has a multi-hole
tube (41) having a plurality of holes (46) formed to penetrate
longitudinally from one end to the other end, first plates (42, 43)
coupled to longitudinal ends of the multi-hole tube (41) and having
through-holes (47) formed to allow adjacent holes (46) to
communicate with each other, and second plates (44, 45) coupled to
the first plates (42, 43) to block the through-holes (47). In this
apparatus, the multi-hole tube (41) and the first and second plates
(42 to 45) constitute the flow paths (60).
[0081] This arrangement allows the flow paths (60) to be easily
formed, thereby making it possible to reduce the manufacturing cost
of the counter-stream-mode oscillating-flow heat transport
apparatus.
[0082] The invention according to fifty-first aspect is
characterized in that the multi-hole tube (41) is fabricated by an
extrusion process or by a drawing process. The invention according
to fifty-second aspect is characterized in that the first plates
(42, 43) are formed into a predetermined shape by pressing.
[0083] The invention according to a fifty-third aspect is
characterized in that the multi-hole tube (41) and the first and
second plates (42 to 45) are joined together by brazing. The
invention according to a fifty-fourth aspect is characterized in
that the first plates (42, 43) are a clad material having a surface
coated with a filler metal. The invention according to a
fifty-fifth aspect is characterized in that the multi-hole tube
(41) and the first and second plates (42 to 45) are made of an
aluminum alloy.
[0084] The invention according to fifty-sixth aspect is
characterized in that a second multi-hole tube (48) having a
different pitch between the adjacent holes (46) is coupled to the
multi-hole tube (41). The invention according to fifty-seventh
aspect is characterized in that the second multi-hole tube (48) is
coupled to the multi-hole tube (41) via a clad material having both
front and rear surfaces coated with a filler metal. The invention
according to a fifty-eighth aspect is characterized in that a
heat-generating element is disposed on a surface of the second
multi-hole tube (48).
[0085] Incidentally, the parenthesized numerals accompanying the
foregoing individual means correspond with numerals in the
embodiments to be described later. Further areas, of applicability
of the present invention will become apparent from the detailed
description provided hereinafter. It should be understood that the
detailed description and specific examples, while indicating the
preferred embodiment of the invention, are intended for purposes of
illustration only and are not intended to limit the scope of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0086] The present invention will become more fully understood from
the detailed description and the accompanying drawings,
wherein:
[0087] FIG. 1 is a partially cutout perspective view showing a
counter-stream-mode oscillating-flow heat transport apparatus
according to a first embodiment of the present invention;
[0088] FIG. 2A is a cross-sectional view showing the main portion
of the counter-stream-mode oscillating-flow heat transport
apparatus according to the first embodiment of the present
invention;
[0089] FIG. 2B is a perspective view showing the main portion of
the counter-stream-mode oscillating-flow heat transport apparatus
according to the first embodiment of the present invention;
[0090] FIG. 3 is a cross-sectional view of line III-III of FIG. 2A
showing the main portion of the counter-stream-mode
oscillating-flow heat transport apparatus according to the first
embodiment of the present invention;
[0091] FIG. 4 is a cross-sectional view of line IV-IV of FIG. 2A
showing the main portion of the counter-stream-mode
oscillating-flow heat transport apparatus according to the first
embodiment of the present invention;
[0092] FIG. 5 is a cross-sectional view showing an oscillating
device according to the first embodiment of the present
invention;
[0093] FIG. 6A is a partially cutout, perspective view showing a
counter-stream-mode oscillating-flow heat transport apparatus
according to a second embodiment of the present invention;
[0094] FIG. 6B is a side view showing a counter-stream-mode
oscillating-flow heat transport apparatus according to the second
embodiment of the present invention;
[0095] FIG. 6C is a cross-sectional view taken along line VIC-VIC
of FIG. 6B showing a counter-stream-mode oscillating-flow heat
transport apparatus according to the second embodiment of the
present invention;
[0096] FIG. 7 is a view showing the counter-stream-mode
oscillating-flow heat transport apparatus according to the second
embodiment of the present invention;
[0097] FIG. 8 is a view showing the counter-stream-mode
oscillating-flow heat transport apparatus according to the second
embodiment of the present invention;
[0098] FIG. 9 is a view showing a counter-stream-mode
oscillating-flow heat transport apparatus according to a third
embodiment of the present invention;
[0099] FIG. 10A is a partially cutout perspective view showing a
counter-stream-mode oscillating-flow heat transport apparatus
according to a fourth embodiment of the present invention;
[0100] FIG. 10B is a view showing a counter-stream-mode
oscillating-flow heat transport apparatus according to a fourth
embodiment of the present invention;
[0101] FIG. 11 is a view showing a counter-stream-mode
oscillating-flow heat transport apparatus according to a fifth
embodiment of the present invention;
[0102] FIG. 12A is a cross-sectional view showing a
counter-stream-mode oscillating-flow heat transport apparatus
according to a sixth embodiment of the present invention;
[0103] FIG. 12B is a cross-sectional view taken along the line
XIIB-XIIB of FIG. 12A showing a counter-stream-mode
oscillating-flow heat transport apparatus according to a sixth
embodiment of the present invention;
[0104] FIG. 13 is a view showing the counter-stream-mode
oscillating-flow heat transport apparatus according to the sixth
embodiment of the present invention;
[0105] FIGS. 14A is a side view showing a counter-stream-mode
oscillating-flow heat transport apparatus according to a seventh
embodiment of the present invention;
[0106] FIG. 14B is a cross-sectional view taken along the line
XIVB-XIVB of FIG. 14A showing a heat-generating portion of a
counter-stream-mode oscillating-flow heat transport apparatus
according to a seventh embodiment of the present invention;
[0107] FIG. 14C is a cross-sectional view taken along the line
XIVC-XIVC of FIG. 14A showing a heat-radiating portion of a
counter-stream-mode oscillating-flow heat transport apparatus
according to a seventh embodiment of the present invention;
[0108] FIG. 15 is a view showing the counter-stream-mode
oscillating-flow heat transport apparatus according to the seventh
embodiment of the present invention;
[0109] FIG. 16A shows a counter-stream-mode oscillating-flow heat
transport apparatus according to an eighth embodiment of the
present invention;
[0110] FIG. 16B is a cross-sectional view taken at line XVIB-XVIB
of FIG. 16A of a counter-stream-mode oscillating-flow heat
transport apparatus according to the eighth embodiment of the
present invention;
[0111] FIG. 17 is a view showing a counter-stream-mode
oscillating-flow heat transport apparatus according to a ninth
embodiment of the present invention;
[0112] FIG. 18A shows a counter-stream-mode oscillating-flow heat
transport apparatus according to a tenth embodiment of the present
invention;
[0113] FIG. 18B shows a counter-stream-mode oscillating-flow heat
transport apparatus according to the tenth embodiment of the
present invention;
[0114] FIG. 19A shows a counter-stream-mode oscillating-flow heat
transport apparatus according to an eleventh embodiment of the
present invention;
[0115] FIG. 19B is a cross-sectional view showing a
counter-stream-mode oscillating-flow heat transport apparatus
according to the eleventh embodiment of the present invention;
[0116] FIG. 20A shows a partially cutout perspective view of a
counter-stream-mode oscillating-flow heat transport apparatus
according to a twelfth embodiment of the present invention;
[0117] FIG. 20B shows a counter-stream-mode oscillating-flow heat
transport apparatus according to the twelfth embodiment of the
present invention;
[0118] FIG. 20C shows a counter-stream-mode oscillating-flow heat
transport apparatus according to the twelfth embodiment of the
present invention;
[0119] FIG. 21 is a view showing a counter-stream-mode
oscillating-flow heat transport apparatus according to a thirteenth
embodiment of the present invention;
[0120] FIG. 22 is an explanatory view showing the operation of a
counter-stream-mode oscillating-flow heat transport apparatus;
[0121] FIG. 23A shows a counter-stream-mode oscillating-flow heat
transport apparatus;
[0122] FIG. 23B is a cross-sectional view taken at line
XXIIIB-XXIIIB of FIG. 23A;
[0123] FIG. 24 is a conceptual view showing the overall
configuration of a heat transport system according to a fourteenth
embodiment;
[0124] FIG. 25 is a cross-sectional view showing the overall
configuration of the heat transport system when viewed from the
mount surface of a heat-generating element according to the
fourteenth embodiment;
[0125] FIG. 26A is a cross-sectional view of the heat transport
apparatus taken at line XXVIA-XXVIA of FIG. 24;
[0126] FIG. 26B is a cross-sectional view of the heat transport
apparatus taken at line XXVIB-XXVIB of FIG. 24;
[0127] FIG. 27A shows a step of forming microchannels in the heat
transport apparatus;
[0128] FIG. 27B shows a step of forming microchannels in the heat
transport apparatus;
[0129] FIG. 28 is a cross-sectional view showing the overall
configuration of a heat transport system according to a fifteenth
embodiment;
[0130] FIG. 29 is a conceptual view showing the overall
configuration of a heat transport system according to a sixteenth
embodiment;
[0131] FIG. 30 is a cross-sectional view showing the overall
configuration of the heat transport system of the configuration of
the heat transport apparatus of FIG. 29 when viewed from the mount
surface of a heat-generating element according to the sixteenth
embodiment;
[0132] FIG. 31 is a conceptual view showing the overall
configuration of a heat transport system according to a seventeenth
embodiment;
[0133] FIG. 32 is a cross-sectional view showing a heat transport
apparatus according to an eighteenth embodiment;
[0134] FIG. 33 is a cross-sectional view showing a variation of the
heat transport apparatus of the eighteenth embodiment;
[0135] FIG. 34A is a view of the configuration of a heat transport
apparatus according to a nineteenth embodiment;
[0136] FIG. 34B is a cross-sectional view of the configuration of a
heat transport apparatus taken at line XXXIVB-XXXIVB of FIG. 34A
according to the nineteenth embodiment;
[0137] FIG. 34C is a cross-sectional view of the configuration of a
heat transport apparatus taken at line XXXIVC-XXXIVC of FIG. 34A
according to the nineteenth embodiment;
[0138] FIG. 35A is a plan view of the configuration of a heat
transport apparatus according to a twentieth embodiment;
[0139] FIG. 35B is a side view of the heat transport apparatus of
FIG. 35A;
[0140] FIG. 35C is a cross-sectional view taken along line
XXXVC-XXXVC of FIG. 35A;
[0141] FIG. 35D is a cross-sectional view taken along line
XXXVD-XXXVD of FIG. 35A;
[0142] FIG. 36A is a cross-sectional view of the configuration of a
heat receiver portion showing the structure before compression
according to a modified example of the twentieth embodiment;
[0143] FIG. 36B is a cross-sectional view of the configuration of a
heat receiver portion showing the structure after compression
according to a modified example of the twentieth embodiment;
[0144] FIG. 37A is a plan view of the configuration of a heat
transport apparatus according to a twenty-first embodiment;
[0145] FIG. 37B is a side view of the configuration of a heat
transport apparatus according to a twenty-first embodiment;
[0146] FIG. 37C is a cross-sectional view taken along line
XXXVIIC-XXXVIIC of FIG. 37B;
[0147] FIG. 38A is an enlarged view of the flow paths of FIG.
37C;
[0148] FIG. 38B is an enlarged view of a modified example of the
flow paths of FIG. 38A;
[0149] FIG. 39 is a perspective view showing the outer appearance
of a counter-stream-mode oscillating-flow heat transport apparatus
30 according to a twenty-second embodiment of the present
invention;
[0150] FIG. 40 is a perspective view of the main portion of the
counter-stream-mode oscillating-flow heat transport apparatus 30
according to the twenty-second embodiment of the present
invention;
[0151] FIG. 41 is a view showing the main portion of the
counter-stream-mode oscillating-flow heat transport apparatus 30
according to the twenty-second embodiment of the present
invention;
[0152] FIG. 42 is a view showing the main portion of a
counter-stream-mode oscillating-flow heat transport apparatus
according to a twenty-third embodiment of the present
invention;
[0153] FIG. 43 is a view showing the main portion of a
counter-stream-mode oscillating-flow heat transport apparatus
according to a twenty-fourth embodiment of the present
invention;
[0154] FIG. 44 is a view showing the main portion of a
counter-stream-mode oscillating-flow heat transport apparatus
according to a twenty-fifth embodiment of the present
invention;
[0155] FIG. 45 is a perspective view showing the outer appearance
of a counter-stream-mode oscillating-flow heat transport apparatus
according to a twenty-sixth embodiment of the present
invention;
[0156] FIG. 46 is a view showing the main portion of the
counter-stream-mode oscillating-flow heat transport apparatus
according to the twenty-sixth embodiment of the present
invention;
[0157] FIG. 47 is an exploded view showing the heat transport
device assembly according to a first manufacturing method of the
prior art.
[0158] FIG. 48 is an exploded view showing the heat transport
device assembly according to a second manufacturing method of the
prior art.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0159] The following description of the preferred embodiments is
merely exemplary in nature and is in no way intended to limit the
invention, its application, or uses.
First Embodiment
[0160] In this embodiment, the present invention is applied to a
cooling device for electronic components. FIG. 1 is a partially
cutout, perspective view showing the outer appearance of a
counter-stream-mode oscillating-flow heat transport apparatus 1
according to this embodiment. FIGS. 2A to 4 are cross-sectional
views showing the main portion of the counter-stream-mode
oscillating-flow heat transport apparatus 1. FIG. 5 is a schematic
view showing an oscillating device 6.
[0161] In FIG. 1, a heat transport device assembly 2 formed
generally in the shape of a swath or strip of plate has serpentine
flow paths 3 occupied by a fluid, and is provided at both
longitudinal ends thereof with heat-radiating portions 4 to be
cooled by cooling water, while incorporating, generally at the
longitudinal center thereof, a heat-generating element 5 or a heat
source that is to be cooled. In this embodiment, the
heat-generating element 5 is intended to represent electronic
components such as integrated circuits of a computer. The
configuration of the heat transport device assembly 2 will be
described later.
[0162] This embodiment employs water as the fluid in the flow paths
3. However, a type of water that is mixed with an additive to
reduce the viscosity thereof may also be utilized. The fluid is
injected through an inlet 2b with the pressure in the flow paths 3
being reduced by a vacuum pump or the like.
[0163] The oscillating device 6 acts as pump means for inducing
oscillations in the fluid in the heat transport device assembly 2,
and as shown in FIG. 5, is adapted to induce oscillations in the
fluid by reciprocating a plunger 6a into which are integrated a
movable element to be displaced by an electromagnetic force and a
piston for creating oscillations in the fluid.
[0164] Springs 6b serve as resilient means for producing a
resilient force to bring the plunger 6a, having been displaced by
an electromagnetic force, to its original position. A thin-film
coating 6c (of thickness about 0.1 mm in this embodiment), which
covers the plunger 6a and is made of resin, is responsible for a
bearing function for making the plunger 6a slidable within a casing
6d and a sealing function for preventing the fluid from flowing
through a gap between the plunger 6a and the casing 6d. An
excitation coil 6e establishes a magnetic field.
[0165] As shown in FIG. 5, outlet ports 6f1 and 6f2 of the
oscillating device 6 are connected to inlet ports 2a (see FIGS. 3
and 4) of the heat transport device assembly 2 via conduits 6g. The
interior of the outlet ports 6f1 and 6f2 are divided into two
channels.
[0166] Now, the heat transport device assembly 2 will be described.
The heat transport device assembly 2 has a plurality of serpentine
flow paths 3 formed therein, which are constructed first by forming
serpentine grooves by etching on metal plates such as copper or
aluminum which have a high thermal conductivity. The plates are
then bonded together by brazing or by thermal compression in the
direction of their thickness to form a stack of the plates with the
grooves formed thereon.
[0167] As shown in FIG. 2B, in this embodiment, the flow paths 3
adjacent to the heat-generating element 5 are disposed
perpendicular to the plate-shaped heat-generating element 5 to
produce oscillatory displacements in the fluid, of the fluids in
the flow paths 3, located near the heat-generating element 5, such
that the fluid is directed toward the heat-generating element 5.
Additionally, turning portions 3a of the serpentine flow paths 3
are disposed so as to face the heat-generating element 5.
[0168] Furthermore, as shown in FIGS. 2A to 4 (particularly, FIG.
2B), the flow paths 3 are in three dimensions with two different
directions parallel to a plate surface 5a of the heat-generating
element 5 and the third direction perpendicular to the plate
surface 5a. The flow paths 3 are stacked in multiple layers in the
direction from the heat-generating element 5 to the flow paths 3
(in the vertical direction D1 shown in FIG. 2A). Additionally, as
shown in FIG. 2A, a plurality of flow paths 3 (eight in this
embodiment) are disposed adjacent to the heat-generating element 5
in the direction of fluid oscillation.
[0169] In the foregoing, the "direction of fluid oscillation"
refers to the direction D2 (see FIG. 2A) leading macroscopically
from the heat-generating element 5 to the heat-radiating portions
4. However, since the flow paths 3 are shown in three dimensions
(loosely in the shape of a crank) in this embodiment, the
directions of fluid oscillation are different microscopically
depending on the position of the flow paths 3.
[0170] Now, the operation or effects of this embodiment will be
described. The oscillating device 6 is operated to create
oscillations of counterflow fluids in adjacent flow paths 3 with a
bounding portion 3b for defining the boundary thereof interposed
therebetween. This allows a high-temperature fluid phase and a
low-temperature fluid phase to periodically oppose each other with
the bounding portion 3b interposed therebetween, thus causing heat
to be transferred in a "frog jump" kind of way as described above.
Accordingly, "hot heat" of the heat-generating element 5 is
transferred from the heat-generating element 5 to the
heat-radiating portions 4 in the direction orthogonal to the
longitudinal direction of the heat transport device assembly 2,
whereas "cold heat" generated in the heat-radiating portions 4 is
transferred from the heat-radiating portions 4 to the
heat-generating element 5 in the direction orthogonal to the
longitudinal direction of the heat transport device assembly 2.
[0171] At this time, oscillatory displacement is imparted to a
fluid located near the heat-generating element 5 as the fluid is
directed toward the heat-generating element 5. This induces an
oscillating movement and turbulence in the fluid at particular
portions of the flow paths 3 corresponding to the heat-generating
element 5. This causes a low-temperature fluid to intermittently
collide against the portion corresponding to the heat-generating
element 5, thereby providing an increased coefficient of heat
transfer between the heat-generating element 5 and the fluid.
[0172] In contrast to this, the prior art counter-stream-mode
oscillating-flow heat transport apparatus imparts oscillatory
displacements to the fluid parallel to the plate surface of a
heat-generating element at the portion of the flow paths
corresponding to the heat-generating element, thus inducing almost
no turbulence and providing a lower coefficient of heat transfer
than this embodiment. This embodiment thus allows a larger quantity
of heat to be collected from the heat-generating element 5 in a
shorter period of time than, say, a prior art counter-stream-mode
oscillating-flow heat transport apparatus, thereby making it
possible to provide improved heat transport capability than the
prior art counter-stream-mode oscillating-flow heat transport
apparatus.
[0173] Furthermore, the turning portions 3a of the serpentine flow
paths 3 are disposed to face the heat-generating element 5. This
ensures the imparting of the oscillating movement and turbulence to
the fluid at a portion of the flow paths 3 corresponding to the
heat-generating element 5, thereby ensuring an improvement in heat
transport capability.
[0174] Still furthermore, the flow paths 3 are crank-shaped, and
the flow paths 3 are stacked in multiple layers in the direction
from the heat-generating element 5 toward the flow paths 3. This
makes it possible to increase the area that contributes to heat
exchange between adjacent flow paths 3 while preventing the heat
transport device assembly 2 from being increased in size, thereby
ensuring an improvement in heat transport capability.
[0175] The fluid exchanges heat with the heat-generating element 5
at a portion of the flow paths 3 corresponding to the
heat-generating element 5, naturally in a manner such that the
greater the difference in temperature between the fluid and the
heat-generating element 5, the more the linear increase in the
quantity of heat exchange becomes. In contrast to this, the
quantity of heat exchange is not linearly increased as the opposing
area between the heat-generating element 5 and the fluid increases,
but becomes saturated against the increase in the opposing
area.
[0176] That is, a maximum temperature difference .DELTA.T is
provided between the fluid and the heat-generating element 5 at an
end of the heat-generating element 5. However, since the quantity
of heat exchange is reduced exponentially in response to an
increase in the opposing area between the heat-generating element 5
and the fluid, an increase in the quantity of heat exchange through
the opposing area between the heat-generating element 5 and the
fluid will become saturated.
[0177] Here, the prior art counter-stream-mode oscillating-flow
heat transport apparatus employs one flow path 3 adjacent to the
heat-generating element 5 in the direction of fluid oscillation,
whereas the counter-stream-mode oscillating-flow heat transport
apparatus according to this embodiment employs a plurality of flow
paths 3 adjacent to the heat-generating element 5 in the direction
of fluid oscillation. Suppose that both the prior art
counter-stream-mode oscillating-flow heat transport apparatus and
the counter-stream-mode oscillating-flow heat transport apparatus 1
according to this embodiment have the same total opposing area. In
this case, the counter-stream-mode oscillating-flow heat transport
apparatus according to this embodiment has a smaller opposing area
per piece than the prior art counter-stream-mode oscillating-flow
heat transport apparatus.
[0178] However, as described above, the increase in the quantity of
heat exchange through the opposing area is saturated. Thus, even
for a reduced opposing area per piece, the arrangement with a
plurality of flow paths 3 adjacent to the heat-generating element 5
can provide, as a whole, an increased quantity of heat to be
absorbed from the heat-generating element 5. Accordingly, it is
possible to ensure improved heat transport capability while
preventing the heat transport device assembly 2 from increasing in
size.
Second Embodiment
[0179] In the fourteenth embodiment, the flow paths 3 are shown in
three dimensions that extend in a plurality of directions in those
dimensions. However, as shown in FIGS. 6A to 8, this embodiment
employs flow paths 3 in two dimensions that extend in a plurality
of directions of those two dimensions.
Third Embodiment
[0180] In the fourteenth embodiment, to employ a plurality of flow
paths 3 adjacent to the heat-generating element 5 in the direction
of fluid oscillation, the flow paths 3 adjacent to the
heat-generating element 5 are disposed generally perpendicular to
the plate surface 5a of the heat-generating element 5, as shown in
FIG. 2A. However, as shown in FIG. 9, this embodiment allows the
flow paths 3 adjacent to the heat-generating element 5 to be
disposed generally parallel to the plate surface 5a of the
heat-generating element 5.
Fourth Embodiment
[0181] In the aforementioned embodiments, the heat-generating
element 5 is in direct contact with the heat transport device
assembly 2 or a member constituting the flow paths 3. However, as
shown in FIG. 10, this embodiment is provided with a heat reservoir
7, for accumulating heat therein, between the heat-generating
element 5 and the flow paths 3 in which the fluid is present that
absorbs heat from the heat-generating element 5. In this
embodiment, a member having a specific heat equal to or greater
than that of the member constituting the flow paths 3 is interposed
between the heat transport device assembly 2 and the
heat-generating element 5, thereby forming the heat reservoir
7.
[0182] Now, the operation or effects of this embodiment will be
described. For electronic components such as integrated circuits in
a computer, their macroscopic, or overall, average temperature
needs to be kept within a predetermined temperature range, and a
sudden variation in temperature in a short period of time may lead
to significant degradation in durability, that is, service
life.
[0183] On the other hand, to collect heat from the heat-generating
element 5 with a high degree of efficiency, a large temperature
difference .DELTA.T is required between the heat-generating element
5 and the fluid. However, oscillatory displacements in the fluid at
a portion of the flow paths 3 corresponding to the heat-generating
element 5 lead to a sudden variation in the temperature difference
.DELTA.T in a short period of time. Therefore, a relatively low
frequency of oscillation needs to be provided for the fluid in
order to prevent a sudden variation in the temperature of the
heat-generating element 5 in a short period of time. However, it is
difficult for this means to ensure an improved heat transport
capability.
[0184] In contrast to this, this embodiment is provided with the
heat reservoir 7 between the heat-generating element 5 and the flow
paths 3 in which the fluid is present that absorbs heat from the
heat-generating element 5. Thus, the heat reservoir 7 serves as a
buffer for accommodating a change in temperature although the heat
transfer from the heat-generating element 5 to the fluid is
retarded by the heat reservoir 7, thereby making it possible to
provide an increased frequency of oscillation for the fluid.
[0185] Accordingly, since the frequency of oscillation of the fluid
can be increased, it is possible to increase the total quantity of
heat transport even when the heat transfer from the heat-generating
element 5 to the fluid is retarded by the heat reservoir 7. It is
also possible to increase the total quantity of heat transport
while reducing the variation in temperature of the heat-generating
element 5.
Fifth Embodiment
[0186] As shown in FIG. 11, this embodiment is a modified example
of the fourth embodiment and provides a portion 3c among the
members constituting the flow paths 3, the portion 3c facing the
heat-generating element 5 and being thicker than the bounding
portion 3b, to form the heat reservoir 7.
Sixth Embodiment
[0187] In the fourteenth embodiment, principally, only the
heat-radiating portions 4 dissipate the heat from the
heat-generating element 5. However, as shown in FIGS. 12A, 12B, and
13, this embodiment is provided with a radiating fin 4a for
enhancing heat exchange between the fluid in the flow paths 3 and
an external fluid (air in this embodiment). This embodiment is
configured such that the flow paths 3 are in communication with an
inside of the radiating fin 4a allowing the flow paths 3 themselves
to serve as a radiating fin. This makes it possible to provide
improved thermal dissipation and thus an increased total heat
transport quantity.
[0188] FIGS. 12A and 12B show an example in which the radiating fin
4a is provided at an end of the heat transport device assembly 2 in
its longitudinal direction. FIG. 13 shows an example in which the
radiating fin 4a is provided on the way of the flow paths 3.
Seventh Embodiment
[0189] In the fourteenth embodiment, to impart oscillatory
displacements to the fluid in a manner such that the fluid located
near the heat-generating element 5 be directed toward the
heat-generating element 5, a portion of the flow paths 3 adjacent
to the heat-generating element 5 is disposed generally
perpendicular to the plate surface 5a of the heat-generating
element 5 with the other portions being disposed generally parallel
to the plate surface 5a of the heat-generating element 5. As shown
in FIGS. 14A through 15, this embodiment is configured such that
the other portions are also disposed generally perpendicular to the
plate surface 5a of the heat-generating element 5 in addition to
the portion of the flow paths 3 adjacent to the heat-generating
element 5.
[0190] In FIGS. 14A to 14C, since the heat-radiating portion 4 is
larger than the portion to which the heat-generating element 5 is
attached, an increased angle of inclination is provided relative to
the normal direction of the plate surface 5a in the vicinity of the
heat-radiating portions 4 along the flow paths 3.
[0191] Furthermore, according to FIGS. 14A through 15, since the
heat-generating element 5 and the heat-radiating portion 4 are
disposed in the direction in which the fluid transports heat, it is
still possible to satisfactorily transport heat from the
heat-generating element 5 to the heat-radiating portion 4 even with
a short distance between the heat-generating element 5 and the
heat-radiating portion 4.
Eighth Embodiment
[0192] In the aforementioned embodiments, heat is exchanged between
adjacent flow paths 3 on a plane parallel to the plate surface 5a.
However, as shown in FIGS. 16A and 16B, this embodiment allows heat
to be exchanged between adjacent flow paths 3 on a plane orthogonal
to the plate surface 5a, thereby providing an increased area
contributing to heat exchange.
[0193] Furthermore, in the aforementioned embodiments, the fluids
in adjacent flow paths 3 are oscillated in the counterflow
directions parallel to each other on a plane parallel to the plate
surface 5a. However, in this embodiment, the fluids in adjacent
flow paths 3 are oscillated in crosswise directions on a plane
orthogonal to the plate surface 5a.
[0194] The fluids in adjacent flow paths 3 on a plane orthogonal to
the plate surface 5a may be oscillated for heat exchange in the
crosswise directions, while the fluids in the adjacent flow paths 3
on a plane parallel to the plate surface 5a may be oscillated in
the counterflow directions parallel to each other, thereby allowing
heat to be exchanged in the two directions.
[0195] Furthermore, as shown in FIGS. 23A and 23B, the flow paths
in contact with the heat-generating element 5 are formed only in
the vicinity of the heat-generating element 5 (e.g., over the width
thereof), so that the fluids in adjacent flow paths are oscillated
in the counterflow directions parallel to each other (allowing heat
to be diffused in one direction).
[0196] Additionally, fluids in flow paths disposed parallel to the
aforementioned flow paths and orthogonal thereto are oscillated in
the counterflow directions orthogonal to the direction in which
heat is allowed to diffuse (causing the heat to diffuse). Since the
counterflow paths are disposed only in the vicinity of the
heat-generating element, the paths can be shortened. Therefore,
reduced power for the operation is required.
Ninth Embodiment
[0197] In the aforementioned embodiments, the heat transport device
assembly 2 is nearly a perfect rigid body. However as shown in FIG.
17, this embodiment is provided with a bounding portion 3b, among
the members constituting the flow paths 3, formed of a metal such
as an annealed copper having good thermal conductivity.
Additionally, portions 3d, separate from the bounding portion 3b,
are formed of a soft material such as resin. This resin potion 3d
can be recessed to accept the metal thin plate 3b. This
construction and these materials allows the heat transport device
assembly 2 to be readily bent just like an electric cord, thereby
facilitating the implementation of the counter-stream-mode
oscillating-flow heat transport apparatus.
Tenth Embodiment
[0198] As shown in FIGS. 18A and 18B, this embodiment provides a
heat transport device assembly 2 having a plurality of serpentine
flow paths 3 therein which are formed by stamping grooves or holes
on a material plate 3e corresponding to the flow paths 3 and then
by brazing or thermally compressing a stack of alternate material
plates 3e and material plates 3f having neither grooves nor
holes.
Eleventh Embodiment
[0199] As shown in FIGS. 19A and 19B, this embodiment provides a
heat transport device assembly 2 having a plurality of serpentine
flow paths 3 therein which are formed by brazing or thermally
compressing a wavy material plate 3h, on which holes 3g are bored,
and plate-shaped material plates 3j.
Twelfth Embodiment
[0200] As shown in FIGS. 20A, 20B, and 20C, this embodiment
provides flow paths 3 that are stacked in multiple layers in the
direction orthogonal to a plane in contact with the heat-generating
element 5. While preventing the counter-stream-mode
oscillating-flow heat transport apparatus 1 from increasing in
size, this embodiment allows the flow paths 3 stacked in multiple
layers to provide an increased area contributing to heat exchange
between adjacent flow paths 3 as well as to ensure an improvement
in heat transport capability.
Thirteenth Embodiment
[0201] In the aforementioned embodiments, the heat transport device
assembly 2 is connected to the oscillating device 6 via the conduit
6g, the interior of which is divided into two sections. However, as
shown in FIG. 21, this embodiment allows the heat transport device
assembly 2 and the oscillating device 6 to be connected to each
other via two conduits 6g, the interior of which is not divided
into two.
Other Embodiments
[0202] The aforementioned embodiments provide the plunger 6a that
is reciprocated to thereby induce oscillatory movements in the
fluid, but the present invention is not limited thereto, and allows
the ends of the flow paths 3 to be squeezed or crushed in order to
induce oscillatory movements in the fluid. This method allows the
sealing mechanism to be eliminated, thereby simplifying the
oscillating device 6.
[0203] Furthermore, the aforementioned embodiments provide the
turning portions 3a to implement the flow paths 3 in a serpentine
structure, but the present invention is not limited thereto, and
allows each of adjacent flow paths 3 to form a closed loop without
fluid communication between the adjacent flow paths 3 via the
turning portion 3a. In this case, for example, since it is
difficult to provide oscillatory movements in a non-compressive
fluid within a closed loop (the flow path 3), air bubbles need to
be mixed with the fluid to permit oscillatory movements in the
fluid within the flow paths 3.
Fourteenth Embodiment
[0204] Now, the present invention will be described below with
reference to FIGS. 24 to 27B in accordance with a fourteenth
embodiment. In this embodiment, a heat transport apparatus
according to the present invention is applied to a cooling device
for electronic components.
[0205] FIG. 24 is a conceptual view illustrating the overall
configuration of a heat transport system 8 incorporating a heat
transport apparatus 100 according to the fourteenth embodiment.
FIG. 25 is a cross-sectional view illustrating the configuration of
the heat transport apparatus 100 of FIG. 24 when viewed from the
mount surface of a heat-generating element (heat source) 200.
[0206] As shown in FIG. 24, the heat transport system 8 includes
the heat transport apparatus 100 for releasing heat from the
heat-generating element 200 of high heat fluxes and a circulation
pump 300 for circulating a fluid (heating medium) through the heat
transport apparatus 100. Preferably, as the heat-generating element
200, it is possible to employ electronic components, such as power
components like amplifiers or IGBTs in telecommunication base
stations or CPUs, which generate high temperatures during
operation.
[0207] In this twenty-fourth embodiment, preferably, as the
material of the heat transport apparatus 100, it is possible to
employ a metal having a high heat-conductivity such as aluminum or
copper. This fourteenth embodiment uses a die-cast aluminum. As the
material of the heat transport apparatus 100, it is also possible
to use a resin material, in the case of which the heat transport
apparatus 100 can be flexibly shaped, thereby improving the ease of
its attachment to a portion complicated in shape.
[0208] The heat transport apparatus 100 has a heat receiver portion
101 which is in contact with the heat-generating element 200. In
the heat transport apparatus 100 according to the twenty-fourth
embodiment, a heat-radiating portion (heat radiating fin) 102 is
formed on the entire surface opposite to the mount surface of the
heat-generating element 200. The heat transport apparatus 100
allows the heat receiver portion 101 to accept heat from the
heat-generating element 200 at a high temperature, and then allows
the heat-radiating portion 102 to release outwardly the heat
received at the heat receiver portion 101. Heat is transferred from
the heat receiver portion 101 to the heat-radiating portion 102 via
a fluid, generally known as the heating medium. As the fluid, it is
possible to use water or LLCs (antifreeze liquids).
[0209] At a position corresponding to the heat-generating element
200 in the heat transport apparatus 100, the heat receiver portion
101 for transferring heat from the heat-generating element 200 to
the fluid is designed to be equal in size to the heat-generating
element 200. The heat receiver portion 101 may be slightly greater
than or slightly smaller than the heat-generating element 200, but
is preferably greater than the heat-generating element 200 in order
to transfer heat efficiently.
[0210] As shown in FIG. 25, a plurality of flow paths 103 are
provided that are parallel to each other within the heat transport
apparatus 100. In this fourteenth embodiment, the flow paths 103
are about 200 mm in length, the entire length of the
heat-generating element 200 being about 30 mm. The flow paths 103
of the heat transport apparatus 100 are approximately several
millimeters (1 to 2 mm in this embodiment) in width (the length
orthogonal to the direction of fluid flow). The circulation pump
(means for driving the fluid) 300 of the fourteenth embodiment is
designed to circulate the fluid in one direction, allowing the
fluid to flow in the same direction (from right to left in FIG. 25)
through all the flow paths 103 of the heat transport apparatus
100.
[0211] FIGS. 26A and 26B are cross-sectional views of the
configuration of the heat transport apparatus 100. FIG. 26A is a
cross-sectional view taken along the line XXVIA-XXVIA of FIG. 24,
and FIG. 26B is a cross-sectional view taken along the line
XXVIB-XXVIB of FIG. 24. As shown in FIGS. 26A and 26B, there are
provided a plurality of microchannel forming portions 104 in each
of the flow paths 103 of the heat receiver portion 101 parallel to
the direction of fluid flow. The microchannel forming portions 104
of the fourteenth embodiment are formed in the shape of a thin
plate. In the heat receiver portion 101, the microchannel forming
portions 104 provide a microstructure to the flow paths 103,
thereby allowing microchannels to be formed. The "microchannel" as
used herein refers to a flow path having a microstructure less than
or equal to 1 mm in width.
[0212] The smaller the flow path area, the larger the heat transfer
area becomes, while the resulting reduced hydrodynamic diameter
(typical diameter) causes the heat transfer coefficient to
increase. However, an excessively reduced size of the
microstructure causes an increase in pressure loss. Thus, it is
preferable to form the microchannel within the range of 0.1 to 0.5
mm in width. The fourteenth embodiment provides microchannels
having a width of 0.3 mm in the heat receiver portion 101.
[0213] FIGS. 27A and 27B show steps of forming microchannels in the
heat transport apparatus 100, FIGS. 27A and 27B being
cross-sectional views both similar to FIG. 26A. As shown in FIG.
27A, the heat transport apparatus 100 includes a cover portion 105
and a base portion 106. The cover portion 105 is integrated, at the
portions thereof corresponding to the heat receiver portion 101,
with the microchannel forming portions 104. The microchannel
forming portions 104 of the fourteenth embodiment are formed in the
shape of a thin plate. The base portion 106 is formed of a die-cast
aluminum on which groove portions 107 are formed to constitute the
flow paths 103.
[0214] As shown in FIG. 27B, the cover portion 105 is placed onto
the base portion 106 so that the microchannel forming portions 104
of the cover portion 105 are fitted into the groove portions 107 of
the base portion 106. The portions at which the cover portion 105
is in contact with the groove portions 107 are jointed together by
brazing, welding, adhesive bonding or the like. This arrangement
allows the microchannel forming portions 104 to provide a
microstructure to the flow paths 103 corresponding to the heat
receiver portion 101 and thereby form microchannels.
[0215] Heat is transferred as follows in the heat transport system
having the aforementioned configuration. First, the heat generated
in the heat-generating element 200 is transferred to the heat
receiver portion 101 in the heat transport apparatus 100. In the
heat receiver portion 101, the heat is transferred from the
microchannel forming portions 104 to the fluid. The fluid is passed
through the flow paths 103 to transfer the heat to the
heat-radiating portion 102, where the heat is outwardly
released.
[0216] As described above, only part of the flow paths 103 of the
heat transport apparatus 100 is formed into microchannels, thereby
making it possible to reduce the manufacturing costs. Upon forming
part of the flow paths 103 into microchannels, the flow paths 103
disposed in the vicinity of the heat-generating element 200 of high
heat fluxes can be formed into microchannels, thereby releasing
heat effectively from the heat-generating element 200. Since only
part of the flow paths 103 is formed into microchannels, it is also
possible to prevent an increase in pressure loss and thereby save
the power of the circulation pump 300. Furthermore, the die-cast
aluminum on which the groove portions 107 are formed is used for
the base portion 106, thereby making it possible to reduce
manufacturing costs when compared with the case where the grooves
are formed by cutting.
Fifteenth Embodiment
[0217] Now, the present invention will be described with reference
to FIG. 28 in accordance with a fifteenth embodiment. The fifteenth
embodiment is different from the fourteenth embodiment in that it
has a different heat transport apparatus flow path structure. The
following description differentiates this embodiment from the
fourteenth embodiment.
[0218] FIG. 28 is a view showing the overall configuration of a
heat transport system 9 according to the second embodiment,
corresponding to FIG. 25 of the aforementioned fourteenth
embodiment. As shown in FIG. 28, a heat transport apparatus 110
according to the fifteenth embodiment is designed such that the
fluid makes U-turns to flow therein. In other words, a fluid
flowing in from the right end of the heat transport apparatus 110
in FIG. 28 passes from right to left and then makes a U-turn at the
left end to flow out of the right end. Such an arrangement can also
provide the same effects as those of the aforementioned fourteenth
embodiment.
Sixteenth Embodiment
[0219] Now, the present invention will be described with reference
to FIGS. 29 and 30 in accordance with a sixteenth embodiment. The
sixteenth embodiment is different from the fourteenth embodiment in
having different configurations of the heat transport apparatus and
the pump. The following description differentiates this embodiment
from the fourteenth embodiment.
[0220] FIG. 29 is a conceptual view showing the overall
configuration of a heat transport system 10 incorporating a heat
transport apparatus 120 according to the sixteenth embodiment. FIG.
30 is a cross-sectional view illustrating the configuration of the
heat transport apparatus 120 of FIG. 29 when viewed from the mount
surface of the heat-generating element 200. FIG. 29 corresponds to
FIG. 24, and FIG. 30 corresponds to FIG. 25.
[0221] As shown in FIGS. 29 and 30, the sixteenth embodiment
employs an oscillator pump 310 as a pump for displacing the fluid
within the heat transport apparatus 120. For example, the
oscillator pump 310 has a piston therein which reciprocates by an
electromagnetic force or the like, thereby imparting an oscillatory
flow of the fluid in flow paths 123 of the heat transport apparatus
120. With the oscillator pump 310 of the sixteenth embodiment, the
cycle and amplitude of the oscillation of the fluid can be set to a
given value. Preferably, from the viewpoint of heat transfer
performance, the fluid has amplitudes on the order of three times
or more the total length of the heat-generating element 200, and in
this embodiment, the amplitude of the fluid is set at about 100 mm
for the heat-generating element 200 having a total length of about
30 mm.
[0222] As shown in FIG. 30, the heat transport apparatus 120
according to the sixteenth embodiment has the flow paths 123 formed
in a serpentine shape. More specifically, a plurality of flow paths
123 parallel to each other is provided, with adjacent flow paths
being in communication with each other at an end. Adjacent flow
paths 123 allow both fluids to be directed in a counterflow
relationship.
[0223] The heat transport apparatus utilizing such an oscillatory
flow allows the oscillation to displace the fluid from a first
point, at which a heat receiver portion 121 accepts heat from the
heat-generating element 200, to a second point at which heat is
transferred to a heat-radiating portion 122. This causes the heat
of the heat-generating element 200 to be transferred from the first
point to the second point just like a frog jumps from one place to
another. Such a heat transfer accompanies the oscillation. Thus,
the higher the frequency of oscillation, the larger the number of
times of "frog jumps" per unit time becomes, while the larger the
amplitude, the greater the distance a frog jump becomes. That is,
the displacement of heat accompanying the oscillation increases
with an increase in amplitude and cycling of the fluid.
[0224] Therefore, increased cycling of the oscillatory flow of the
fluid makes it possible to improve heat transport performance,
while decreased cycling makes it possible to reduce heat transport
performance. Likewise, an increased amplitude of the oscillatory
flow of the fluid makes it possible to improve heat transport
performance, while a reduced amplitude makes it possible to reduce
heat transport performance. The heat transport apparatus 120
employing oscillatory flow controls the frequency and amplitude of
the fluid as described above, thereby facilitating the adjustment
of the heat transport performance over a wide range.
Seventeen Embodiment
[0225] Now, the present invention will be described with reference
to FIG. 31 in accordance with a seventeenth embodiment. The
seventeenth embodiment is different from the sixteenth embodiment
in that it has a different heat transport apparatus configuration.
The following description differentiates this embodiment from the
third embodiment.
[0226] FIG. 31 is a conceptual view illustrating the overall
configuration of a heat transport system 11 incorporating a heat
transport apparatus 130 according to the seventeenth embodiment,
corresponding to FIG. 29 of the sixteenth embodiment. As shown in
FIG. 31, the heat transport apparatus 130 according to the
seventeenth embodiment is designed such that a heat receiver
portion 131 and a heat-radiating portion 132 are separate. More
specifically, the heat receiver portion 131 for accepting heat from
the heat-generating element 200 is formed at an end (at the left
end of FIG. 31) of the heat transport apparatus 130, while the
heat-radiating portion 132 is formed at the other end of the heat
transport apparatus 130 (at the right end in FIG. 31). The
heat-radiating portion 132 is also formed on a portion on the same
side as the mount surface of the heat-generating element 200 in the
heat transport apparatus 130 as well as on a portion on the
opposite side to the mount surface of the heat-generating element
200. Such an arrangement can also provide the same effects as those
of the sixteenth embodiment.
Eighteenth Embodiment
[0227] Now, the present invention will be described with reference
to FIGS. 32 and 33 in accordance with an eighteenth embodiment. The
eighteenth embodiment is different from the fourteenth embodiment
in the method for forming microchannels. The following description
differentiates this embodiment from the fourteenth embodiment.
[0228] FIGS. 32 and 33 are cross-sectional views illustrating heat
transport apparatuses 140, 150, corresponding to FIG. 27B of the
fourteenth embodiment. As shown in FIGS. 32 and 33, in the
eighteenth embodiment, there are provided base portions 146, 156 as
sides in contact with the heat-generating element 200, with cover
portions 144, 154 disposed opposite to the heat-generating element
200. The cover portions 144, 154 are provided with heat-radiating
portions 142, 152.
[0229] As shown in FIGS. 32 and 33, microchannel forming portions
145, 155 according to the eighteenth embodiment employ rod-like
members (elongated bars) formed separately from the cover portions
144, 154. FIG. 32 shows an example of flow paths 143 each having
one rod-like member 145 inserted therein, while FIG. 33 shows
another example of flow paths 153 each having two rod-like members
155 inserted therein. The rod-like members 145, 155 are inserted
along their longitudinal direction in the direction of fluid
flow.
[0230] The rod-like members 145, 155 are inserted into the flow
paths 143, 153 as described above, thereby making it possible to
easily provide a microstructure to the flow paths 143, 153 to form
microchannels. Preferably, when the cover portions 144, 154 are
secured to the base portions 146, 156, the rod-like members 145,
155 are compressed enough to be slightly crushed, thereby securing
the rod-like members 145, 155. This makes it possible to secure the
rod-like members 145, 155 to the base portions 146, 156 in thermal
contact therewith, thereby providing an improved heat transfer
coefficient. It is also possible to obtain the same effects using a
hollow tubular member (an elongated tube) in place of the rod-like
members 145, 155.
Nineteenth Embodiment
[0231] Now, the present invention will be described with reference
to FIGS. 34A to 34C in accordance with a nineteenth embodiment. The
nineteenth embodiment is different from the fourteenth embodiment
in that it has a different heat transport apparatus. The following
description differentiates this embodiment from the fourteenth
embodiment.
[0232] FIGS. 34A, 34B, and 34C are views of the configuration of a
heat transport apparatus 160 according to the nineteenth
embodiment. FIG. 34A is a plan view showing the heat transport
apparatus 160, FIG. 34B is a cross-sectional view taken along the
line XXXIVB-XXXIVB of FIG. 34A, and FIG. 34C is a cross-sectional
view taken along the line XXXIVC-XXXIVC of FIG. 34A. In FIGS.
34A-34C, the heat-radiating portion is not shown.
[0233] The heat transport apparatus 160 according to the nineteenth
embodiment employs an extruded tube of aluminum having multiple
holes. It is possible to extrude aluminum to form a series of
rectangular cross-sectional openings to obtain the extruded tube of
aluminum, which can thus be fabricated at a low cost. The extruded
tube of aluminum 160 has a plurality of through-holes formed
parallel to each other, which constitute flow paths 163 through
which a fluid passes. The through-holes have a width on the order
of 1 mm.
[0234] In the nineteenth embodiment, a heat receiver portion 161 of
the heat transport apparatus 160 is compressed in a direction
parallel to its width (in the length-wise direction of the page in
FIG. 34A), thereby forming the flow paths 163 of the heat receiver
portion 161 into microchannels. As described above, an inexpensive
extruded tube of aluminum is used as the heat transport apparatus
160 and part of it is compressed to form the flow paths 163 into
microchannels, thereby making it possible to provide the heat
transport apparatus 160 at a low cost which has the flow paths 163
formed into microchannels.
Twentieth Embodiment
[0235] Now, the present invention will be described with reference
to FIGS. 35A through 36B in accordance with a twentieth embodiment.
The twentieth embodiment is different from the nineteenth
embodiment because it has a different configuration of the heat
transport apparatus. The following description differentiates this
embodiment from the nineteenth embodiment.
[0236] FIGS. 35A through 35D are views of the configuration of a
heat transport apparatus 170 according to the twentieth embodiment.
FIG. 35A is a plan view showing the heat transport apparatus 170,
FIG. 35B is a side view showing the heat transport apparatus 170,
FIG. 35C is a cross-sectional view taken along the line XXXVC-XXXVC
of FIG. 35A, and FIG. 35D is a cross-sectional view taken along the
line XXXVD-XXXVD of FIG. 35A. In FIGS. 35A-35D, the heat-radiating
portion is not shown. In the twentieth embodiment, a heat receiver
portion 171 of the heat transport apparatus (that is, an extruded
tube of aluminum) 170 is compressed vertically (in the vertical
direction of the page in FIG. 35B), thereby providing a
microstructure to the flow paths 173 of the heat receiver portion
171 to form microchannels.
[0237] On the other hand, the cross-sectional arrangement of the
extruded tube of aluminum may be changed to an example shown in
FIGS. 36A and 36B. FIGS. 36A and 36B are cross-sectional views of
the configuration of the heat receiver portion 171. FIG. 36A shows
the structure before compression, and FIG. 36B shows the structure
after compression. Shown in FIG. 36A is an extruded tube of
aluminum having a bounding portion for defining the boundary of
adjacent flow paths 173, the bounding portion being bent in a "V"
shape. The extruded tube of aluminum is then compressed vertically
(in the vertical direction of the page in FIG. 36A), thereby making
it possible to provide a stable shape after the compression, as
shown in FIG. 36B. Such an arrangement can also provide the same
effects as those of the nineteenth embodiment.
Twenty-First Embodiment
[0238] Now, the present invention will be described with reference
to FIGS. 37A through 38B in accordance with a twenty-first
embodiment. The twenty-first embodiment is different from the
nineteenth embodiment in that it has a different heat transport
apparatus configuration. The following description differentiates
this embodiment from the nineteenth embodiment.
[0239] FIGS. 37A to 37C are views of the configuration of a heat
transport apparatus 180 according to the twenty-first embodiment,
FIG. 37A is a plan view showing the heat transport apparatus 180,
FIG. 37B is a side view showing the heat transport apparatus 180,
FIG. 37C is a cross-sectional view taken along the line
XXXVIIC-XXXVIIC of FIG. 37A. In FIGS. 37A-37C, the heat-radiating
portion is not shown.
[0240] In the example shown in FIGS. 37A-37C, a tubular member (an
elongated tube) is inserted into a flow path 183 in a heat receiver
portion 181 of a heat transport apparatus (extruded tube of
aluminum) 180, and thereafter the flow paths 183 in the heat
receiver portion 181 are compressed vertically, that is, in the
vertical direction of the page in FIG. 37B, and thereby provided
with a microstructure and formed into microchannels. The tubular
members inserted and compressed thereafter can be secured to the
heat transport apparatus 180 in thermal contact therewith, thereby
providing an improved heat transfer coefficient.
[0241] FIGS. 38A and 38B illustrate enlarged views of the flow path
183 of FIG. 37C, FIG. 38A showing an example of one tubular member
inserted into the flow path 183, FIG. 38B showing an example of
four tubular members inserted into the flow path 183. In place of
the tubular member, a rod-like member may also be used. Such an
arrangement can provide the same effects as those of the nineteenth
embodiment.
Other Embodiments
[0242] In the aforementioned eighteenth and twenty-first
embodiments, the tubular member or the rod-like member is inserted
into the flow paths of the heat transport apparatus, thereby
forming the flow paths into microchannels; however, a hollow metal
piece may also be inserted therein in place of the tubular member
and the rod-like member. The hollow metal piece would have cavities
therein, which are in communication from one end to the other. For
example, as the hollow metal piece, it is possible to employ a
foamed metal, a sintered metal, or a metal formed by thermal
spraying.
[0243] For example, to obtain the foamed metal, a gas is blown into
a molten metal or a foaming agent is mixed therewith. To form the
sintered metal, metal powder is sintered. However, for example, a
copper rod-like member having a lower melting point than that of
iron may be inserted into iron powder so as to melt the copper
during sintering, thereby making it possible to readily form
cavities that are in communication from one end to the other. To
form a metal by thermal spraying, a molten metal is sprayed to form
cavities during the spraying.
Twenty-Second Embodiment
[0244] In this embodiment, the present invention is applied to a
cooling device for electronic components. FIG. 39 is a perspective
view showing the outer appearance of a counter-stream-mode
oscillating-flow heat transport apparatus according to this
embodiment. FIGS. 40 and 41 are views showing the main portion of
the counter-stream-mode oscillating-flow heat transport apparatus
30 according to this embodiment.
[0245] Referring to FIG. 39, a heat transport device assembly 40
formed generally in the shape of a strip plate has serpentine flow
paths 60 (see FIG. 41) which are filled by a fluid and are provided
generally at the longitudinal center on the plate surface with
heat-generating elements 70 or heat sources which are to be cooled.
The structure of the heat transport device assembly 40 will be
discussed later. In this embodiment, the heat-generating element 70
is intended to represent electronic components such as integrated
circuits for use in a computer.
[0246] In the heat transport device assembly 40, a heat sink 80 is
provided on the plate surface opposite to the surface having the
heat-generating elements 70. The heat sink 80 has a plurality of
radiating fins 5a, each shaped into a thin plate to radiate the
heat having been transported from the heat-generating elements 4,
or a hot region, into the air, or a cold region. An oscillating
device 6 acts as a pump means for inducing oscillations in the
fluid in the heat transport device assembly 40 and is adapted to
induce oscillations in the fluid by reciprocating a plunger which
includes a movable element to be displaced by an electromagnetic
force and a piston for creating oscillations in the fluid. This
embodiment employs water as the fluid occupying the flow paths 60;
however, a type of water that is mixed with an additive to reduce
the viscosity thereof may also be utilized.
[0247] Now, the heat transport device assembly 40 will be described
with reference to FIGS. 40 and 41. The heat transport device
assembly 40 is formed by joining together the multi-hole tube 41
and first and second plates 42 to 45 which are made of a high
thermal conductivity metal material such as copper or aluminum.
[0248] As used herein, the term "brazing" refers to a technique for
joining materials together using a brazing material or solder
without melting a base material, for example, as described in the
"Bonding and Jointing Techniques" (Tokyo Denki University Press).
More specifically, "brazing" refers to jointing using a filler
metal having a melting point of 450.degree. C. or greater while the
filler metal employed for this purpose is referred to as the
brazing material. "Soldering" refers to jointing using a filler
metal having a melting point of 450.degree. C. or less while the
filler metal employed for this purpose is referred to as the
solder.
[0249] The multi-hole tube 41 is a flat tube that is shaped by an
extrusion process or a drawing process and contains therein a
plurality of holes 46 which are provided at the same time as
shaping and which penetrate from one end to the other end along the
length of the tube. The first plates 42, 43 are provided with
through-holes 47 for allowing adjacent holes 46 to communicate with
each other and are fabricated by pressing a clad material having
front and rear surfaces coated with a filler metal (e.g. a brazing
material).
[0250] The second plates 44, 45 are intended to block the
through-holes 47 at the side of the first plates 42, 43 opposite to
the multi-hole tube 41. The second plates 44, 45 are fabricated by
pressing a non-clad material in this embodiment. The first plates
42, 43 are sandwiched between the second plates 44, 45 and the
multi-hole tube 41 at the longitudinal ends of the multi-hole tube
41, respectively, to join the multi-hole tube 41 and the first and
second plates 42 to 45 together, thereby forming the heat transport
device assembly 40 having serpentine flow paths 60.
[0251] In this embodiment, since the oscillating device 90 is
connected to the left side, with respect to the page, the second
plate 45 is connected with joint pipe portions 91 for coupling the
oscillating device 90 to the heat transport device assembly 40.
[0252] Now, general operation of the counter-stream-mode
oscillating-flow heat transport apparatus 30 according to this
embodiment will be described below. When the oscillating device 90
induces oscillations in a fluid within the flow paths 60 (the heat
transport device assembly 40), heat is exchanged between the fluids
present in adjacent flow paths 60. Thus, the heat from the
heat-generating elements 70, disposed generally at the center of
the length of the heat transport device assembly 40, is transported
towards the longitudinal ends of the heat transport device assembly
40, and spreads throughout the heat transport device assembly 40.
The heat spread throughout the heat transport device assembly 40 is
released into the air via the heat sink 80.
[0253] Now, the operation and effect of this embodiment will be
described below. In this embodiment, the multi-hole tube 41 having
a plurality of holes 46 formed to penetrate from one end to the
other end along the length of the tube, and the second plates 44,
45 for blocking the first plates 42, 43 having the through-holes
47, which allow adjacent holes 46 to communicate with each other,
are joined together, thereby constituting the heat transport device
assembly 40 having serpentine flow paths 60. For this reason, it is
possible to reduce the manufacturing cost of the heat transport
device assembly 40 when compared with the counter-stream-mode
oscillating-flow heat transport apparatus having the structure as
shown in FIGS. 48 and 49.
Twenty-Third Embodiment
[0254] As shown in FIG. 42, this embodiment allows the pitch of
those adjacent holes 46 located at a portion where the
heat-generating elements 70 are attached to the heat transport
device assembly 40 to be less than that of the adjacent holes 46
located at the other portions, thereby increasing the heat transfer
coefficient and heat transfer area to provide improved heat
absorption and dissipation capability. In this context, this
embodiment is designed to join together two types of multi-hole
tubes 41, 48 having different pitches, thereby allowing the pitch
of the holes located at a portion, to which the heat-generating
elements 70 are attached, to be less than that of the holes located
at the other portions.
[0255] In this embodiment, the multi-hole tubes 41, 48 are both
fabricated by an extrusion, process or by a drawing process, thus
making it difficult to provide a filler metal to the multi-hole
tubes 41, 48. Accordingly, there is disposed a joint plate 49 clad
with a filler metal on both the front and rear surfaces thereof
between the multi-hole tube 41 and the multi-hole tube 48, thereby
joining the multi-hole tubes 41, 48 together.
Twenty-Fourth Embodiment
[0256] As shown in FIG. 43, this embodiment is different from the
twenty-second and twenty-third embodiments in that the flow paths
60 (the heat transport device assembly 40) have a larger serpentine
pitch (serpentine cycle). That is, the flow paths 60, according to
this embodiment, make a U-turn once on the right side, with respect
to the page, whereas the flow paths 60 according to the
twenty-second and twenty-third embodiments (see FIGS. 41 and 42)
make U-turns four times on the right side, with respect to the
page.
Twenty-Fifth Embodiment
[0257] As shown in FIG. 44, this embodiment is designed such that
the twenty-third embodiment is applied to the heat transport device
assembly 40 according to the twenty-fourth embodiment. More
specifically, the flow paths 60 make a U-turn once on the right
side, with respect to the page, and the pitch of those adjacent
holes 46 located at a portion to which the heat-generating elements
70 are attached is less than that of the adjacent holes 46 located
at the other portions.
Twenty-Sixth Embodiment
[0258] As shown in FIGS. 45 and 46, this embodiment is designed
such that the heat-generating elements 70 are disposed at a
longitudinal end of the heat transport device assembly 40 while the
heat sink 80 is disposed only at the other longitudinal end of the
heat transport device assembly 40.
[0259] That is, when the oscillating device 90 induces oscillations
of counterflow fluids in the flow paths 60, the heat from the
heat-generating elements 70 transfers away from the heat-generating
elements 70. In this context, this embodiment allows the
heat-generating elements 70 to be disposed at a longitudinal end of
the heat transport device assembly 40 and the heat sink 80 to be
disposed at the other longitudinal end of the heat transport device
assembly 40, thereby making it possible to efficiently cool the
heat-generating elements 70 while reducing the manufacturing cost
of the counter-stream-mode oscillating-flow heat transport
apparatus 30.
Other Embodiments
[0260] In the aforementioned embodiments, the first plates 42, 43
are made of a clad material having the front and rear surfaces
coated with a filler metal, however, the present invention is not
limited thereto. For example, the first plates 42, 43 and the
second plates 44, 45 may be made of a clad material having only one
side coated with a filler metal. Additionally, the multi-hole tube
41 and the first plates 42, 43 may be brazed with the filler metal
of the first plates 42, 43, while the first plates 42, 43 and the
second plates 44, 45 may be brazed with the filler metal of the
second plates 44, 45.
[0261] Furthermore, in the aforementioned embodiments, the brazing
was performed using the filler metal coated on the clad material;
however, the present invention is not limited thereto. For example,
the filler metal may be sprayed or applied to the brazed face, or
alternatively, a brazing sheet may be disposed at the brazed face,
thereby eliminating the joint plate 49.
[0262] On the other hand, in the aforementioned embodiments, the
plate surfaces of the radiating fins 81 are generally parallel to
the flow of cooling air while the oscillating device 90 is disposed
at a position displaced from the flow of the cooling air passing
through the heat sink 80, but the present invention is not limited
thereto.
[0263] The description of the invention is merely exemplary in
nature and, thus, variations that do not depart from the gist of
the invention are intended to be within the scope of the invention.
Such variations are not to be regarded as a departure from the
spirit and scope of the invention.
* * * * *
References