U.S. patent application number 12/919126 was filed with the patent office on 2011-01-06 for fan and cooling device.
Invention is credited to Shailesh N. Joshi, Punan Tang.
Application Number | 20110000654 12/919126 |
Document ID | / |
Family ID | 41016363 |
Filed Date | 2011-01-06 |
United States Patent
Application |
20110000654 |
Kind Code |
A1 |
Joshi; Shailesh N. ; et
al. |
January 6, 2011 |
FAN AND COOLING DEVICE
Abstract
A cooling device having a first fan, a second fan upstream of
the first fan, and a flow conditioner element that includes a
housing with a first side having a flow-conditioner plate, a second
side opposite the first side that defines an opening, and a duct
between the first side and the second side, wherein the
flow-conditioner plate is attached to a side of the first fan
proximal to the second fan and the second side of the housing is
attached to a side of the second fan proximal to the first fan. A
method for cooling electronic components and a fan assembly are
also disclosed.
Inventors: |
Joshi; Shailesh N.;
(Houston, TX) ; Tang; Punan; (Houston,
TX) |
Correspondence
Address: |
HEWLETT-PACKARD COMPANY;Intellectual Property Administration
3404 E. Harmony Road, Mail Stop 35
FORT COLLINS
CO
80528
US
|
Family ID: |
41016363 |
Appl. No.: |
12/919126 |
Filed: |
February 26, 2008 |
PCT Filed: |
February 26, 2008 |
PCT NO: |
PCT/US08/02523 |
371 Date: |
August 24, 2010 |
Current U.S.
Class: |
165/121 |
Current CPC
Class: |
G06F 1/20 20130101 |
Class at
Publication: |
165/121 |
International
Class: |
F28F 13/00 20060101
F28F013/00 |
Claims
1. A cooling device comprising: a first fan; a second fan upstream
of the first fan; and a flow conditioner element located between
the first and second fans, the flow conditioner element comprising:
a housing having a first side that includes a flow-conditioning
plate; a second side opposite the first side that defines an
opening; and a duct between the first side and the second side,
wherein the flow-conditioning plate is attached to a side of the
first fan proximal to the second fan and the second side of the
housing is attached to a side of the second fan proximal to the
first fan.
2. The cooling device of claim 1, wherein the first and second fans
are axial fans.
3. The cooling device of claim 1, wherein the flow-conditioning
plate has a thickness of approximately 4 mm.
4. The cooling device of claim 3, wherein the flow-conditioning
plate is a perforated plate.
5. The cooling device of claim 4, wherein the perforated plate has
a plurality of circular openings, each having a diameter of
approximately 5 mm.
6. The cooling device of claim 1, wherein: the side of the first
fan proximal to the second fan has a length and a width; and the
flow-conditioning plate has a length that is equal to the length of
the side of the first fan and a width that is equal to the width of
said side.
7. The cooling device of claim 1, wherein the duct between the
flow-conditioning plate and the second side is an elongated duct
having a length of at least 13 mm.
8. The cooling device of claim 1, wherein the flow conditioner is
manufactured from a rigid plastic or like material.
9. The cooling device of claim 1, wherein an air gap exists between
the flow-conditioning plate and the second fan.
10. A method of cooling electronic components within an enclosure,
the method comprising: generating an air flow from a second fan;
drawing the air flow from the second fan through an opening in a
housing positioned downstream of the second fan; pulling the air
flow through a flow-conditioner plate on a side of the housing
distal to the second fan into a first fan attached to the
flow-conditioner plate; and generating the air flow downstream from
the first fan.
11. The method of claim 10, comprising providing the
flow-conditioner plate with a plurality of perforations.
12. The method of claim 10, comprising locating the
flow-conditioner plate adjacent the first fan.
13. The method of claim 10, comprising providing the
flow-conditioner plate having a thickness of approximately 4
mm.
14. A fan assembly for cooling electronic components, the fan
assembly comprising: a fan; an inlet duct having: a first end
upstream of the fan, said first end defining a first opening having
a first diameter; and a second end downstream of the first end,
said second end attached to a first side of the fan and defining a
second opening having a second diameter that is smaller than the
first diameter; an outlet duct having: a first end attached to a
second side of the fan opposite the first side, said first end of
the outlet duct defining an opening having a first diameter, and a
second end downstream of the first end, said second end defining a
second opening having a second diameter that is greater than the
first diameter.
15. The fan assembly of claim 14, wherein: the diameter of the
first end of the inlet duct is equal to the diameter of the second
end of the outlet duct; and the diameter of the second end of the
inlet duct is equal to the diameter of the first end of the outlet
duct.
16. The fan assembly of claim 14, wherein the second end of the
outlet duct is attached to a flow conditioner element, the flow
conditioner element comprising: a housing having a first side that
includes a flow-conditioning plate; a second side opposite the
first side that defines an opening; and a duct between the first
side and the second side, wherein the flow-conditioning plate is
attached to a side of the first fan proximal to the second fan and
the second side of the housing is attached to a side of the second
fan proximal to the first fan.
17. The fan assembly of claim 14 wherein the fan is an axial fan.
Description
BACKGROUND
[0001] When in operation, electronic components generate heat which
must be dissipated in order to ensure their continued operation and
to prevent the build up of heat within the device or cabinet in
which the electronic components are located. This is particularly
true with respect to computer components used in desktops or
servers where the increasing density of components has resulted in
increased cooling demands.
[0002] The increased cooling demands can be met by supplying higher
airflow through the device or system in which the components are
located. Due to space limitations in various devices, including
desktops and servers, the installation of larger or parallel fans
is not practicable. One alternative to the use of parallel fans is
to use series stacked fans to provide for higher rates of airflow.
Unfortunately, the performance of the stacked series fans is
reduced due to the non-ideal i.e., non-uniform entrance flow of air
entering the downstream fan.
[0003] Various attempts have been made to improve the flow of air
entering the downstream fan. These include the use of outlet guide
vanes attached to the upstream fan in an attempt to provide uniform
airflow to the downstream fan. Additionally, an air gap has been
provided between the upstream and downstream fans in an attempt to
provide uniform airflow.
[0004] Given the need to provide a greater amount of cooling for
more concentrated electronic components, a device that could
generate a larger amount of cooling air at a reduced noise level
would be an important improvement in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a sectional view of a cooling device showing a
first and second fan and a flow conditioner.
[0006] FIG. 2 is a side view of a flow conditioner.
[0007] FIG. 3 is a perspective view of a flow conditioner.
[0008] FIG. 3A is a perspective view of a flow-conditioner
plate.
[0009] FIG. 4 is a graph showing the increase in air flow for a
given static pressure.
[0010] FIG. 5 is a front view of a flow-conditioner plate.
[0011] FIG. 5A is a perspective view of the flow-conditioner plate
shown in FIG. 5.
[0012] FIG. 6 is a graph showing the increased air flow at a given
static pressure using a flow-conditioner plate as shown in FIG.
5.
[0013] FIG. 7 is a table showing the decrease in noise level using
the flow conditioner.
[0014] FIG. 8 is a graph showing the decrease in noise level at
various frequencies using the flow conditioner.
[0015] FIG. 9 is a side view of a fan assembly.
[0016] FIG. 10 is a table showing the increase in flow rate at a
given static pressure for an embodiment of the fan assembly.
[0017] FIG. 11 is a perspective view of an embodiment of a fan
inlet duet.
[0018] FIG. 11A is a perspective view showing the fan connection
plate of the fan inlet duct shown in FIG. 11.
[0019] FIG. 12 is a perspective view of an embodiment of a fan
outlet duct.
[0020] FIG. 12A is a perspective view showing the fan connection
plate of the fan outlet duct shown in FIG. 12.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0021] The apparatus involves a cooling device 10 for use with
electronic components (not shown), in particular, computer
components within desktops, blade enclosures, and servers. As shown
in FIG. 1, the cooling device 10 comprises a first fan 12, a second
fan 14 upstream of the first fan 12, and a flow conditioner element
16 that comprises a housing 18 having a first side 20 that includes
a flow-conditioner plate 22, a second side 24 opposite the first
side 20 that defines an opening 26, and duct 28 between the first
side 20 and the second side 24, wherein the flow-conditioner plate
22 is attached to a side of the first fan 12 proximal to the second
fan 14 and the second side 24 of the housing 18 is attached to a
side of the second fan 14 proximal to the first fan 12.
[0022] In an embodiment, the first 12 and second 14 fans are axial
fans.
[0023] In an embodiment, the flow-conditioner plate 22 has a
thickness "t", as shown in FIG. 2, of approximately 4 mm. This
flow-conditioner plate 22 may be a perforated plate, as is shown in
FIG. 3A. Such a plate defines a plurality of openings 30, each one
of which may be circular with a diameter of approximately 5 mm, in
a particular embodiment. In an embodiment, the flow-conditioner
plate 22 may have a circular grating that is divided into multiple
sections as is shown in FIGS. 5 and 5A.
[0024] In still another embodiment, the length and width of the
side of the first fan 12 proximal to the second fan 14 is equal to
the length and width of the flow-conditioner plate 22. The duct 28,
defined by the housing 18 between the flow-conditioner plate 22 and
the second side 24, may be an elongated duct 28 having a length "L"
of at least 13 mm, as shown in FIG. 2. The duct 28 provides for an
air gap that exists between the flow-conditioner plate 22 and the
second fan 14, as shown in FIGS. 1, 2, and 3.
[0025] The flow conditioner element 16 may be manufactured of
plastic or any like material.
[0026] When in operation, the flow conditioner 16 is aligned
axially between the first and second fan 12, 14, downstream of the
second fan 14, as shown in FIG. 1. Air flow "A" exits the second
fan 14 and proceeds through the opening 26 in the second end 24 of
the flow conditioner housing 18, through the air duct 28 to the
flow-conditioner plate 22 on the first end 20 of the housing 18
adjacent to the first fan 12. The air "A" is then drawn through the
flow-conditioner plate 22 into the first fan 12.
[0027] In an embodiment, the cooling device 10 is used to cool
computer components (not shown) that may be located in a desktop
computer or a server. The flow conditioner 16 improves the flow of
air entering the downstream or first fan 12 by generating a more
uniform flow of air. As can be seen in FIG. 4, using the flow
conditioner results in a higher flow rate in cubic feet per minute
("CFM") being generated by a fan at a given static pressure. This
results in an increase in the airflow through the electronic
components resulting in greater cooling while the spacing of the
fans 12, 14 reduce the noise associated with the airflow through
the fans 12, 14. This increase in air flow allows for an increase
of the density of components in a given compartment as greater
cooling is achieved at a given static pressure than without the use
of the flow conditioner 16. Likewise, the flow conditioner 16
results in an increase in energy savings and noise reduction as it
allows for a particular static pressure to be achieved using a
lower CFM, and thus a lower fan RPM, than a cooling system
utilizing cooling fans arranged is series without a flow
conditioner 16.
[0028] FIGS. 5 and 5A show another embodiment of the
flow-conditioner plate 22 used with the cooling device 10. FIG. 6
is a graph showing the increase in flow rate for a given static
pressure that result from the use of a flow conditioner 16 with the
flow-conditioner plate 22 shown in FIG. 5.
[0029] As shown in FIGS. 7 and 8, at low operating frequencies, the
greater the air gap between the two fans 12, 14, the lower the
noise level. At higher frequencies, an air gap of at least 13 mm
results in a more effective level of noise reduction.
[0030] Also disclosed is a method of cooling electronic components
within an enclosure, the method comprises: (1) generating an air
flow from a second fan 14; (2) drawing the air flow from the second
fan 14 through an opening 26 in a housing 18 positioned downstream
of the second fan 14; (3) pulling the air flow through a
flow-conditioner plate 22 on a side of the housing 18 distal to the
second fan 14 into a first fan 12 attached to the flow-conditioner
panel 22; and (4) generating the air flow downstream from the first
fan 12.
[0031] In an embodiment, the flow-conditioner plate is a perforated
plate.
[0032] A fan assembly 32 for cooling electronic components is also
disclosed. In an embodiment, as shown in FIG. 9, the fan assembly
32 comprises a fan 34; an inlet duct 36 having a first end 38
upstream of the fan 34, said first end 38, as shown in FIGS. 11 and
11A, defines a first opening 40 having a first diameter d.sub.1 and
a second end 42 downstream of the first end 38, said second end 42
attached to a first side 44 of the fan 34 and defining a second
opening 46 having a second diameter d.sub.2 that is smaller than
the first diameter d.sub.1. An outlet duct 48, as shown in FIGS. 12
and 12A, has a first end 50 attached to a second side 52 of the fan
34 opposite the first side 42, said first end 50 of the outlet duct
48 defining an opening 54 having a first diameter d.sub.3; and a
second end 56 downstream of the first end 50, said second end 56
defining a second opening 58 having a second diameter d.sub.4 that
is greater than the first diameter d.sub.4.
[0033] The inlet duct 36, as shown in FIG. 11, used in the assembly
32 creates a nozzle effect that allows for a smoother flow of air
into the fan 34. The outlet duct 48, as shown in FIG. 12, acts as a
diffuser expanding the air flow out of the fan 34. As shown in FIG.
10, the use of the inlet and outlet duct 36, 48 allows for a
greater flow of air at a given static pressure, as shown in FIG.
10, thereby increasing the cooling effect of the fan 34.
[0034] In an embodiment, the diameter d.sub.1 of the first end 38
of the inlet duct 36 is equal to the diameter d.sub.4 of the second
end 56 of the outlet duct 48, and the diameter d.sub.2 of the
second end 42 of the inlet duct 36 is equal to the diameter d.sub.3
of the first end 50 of the outlet duct 48.
[0035] In still another embodiment, the second end of the outlet
duct 56 is attached to a flow conditioner element 16.
[0036] The use of the terms "a" and "an" and "the" and similar
referents in the context of describing the claimed apparatus,
device, system, or method (especially in the context of the
following claims) are to be construed to cover both the singular
and the plural, unless otherwise indicated herein or clearly
contradicted by context. Recitation of ranges of values herein are
merely intended to serve as a shorthand method of referring
individually to each separate value falling within the range,
unless otherwise indicated herein, and each separate value is
incorporated into the specification as if it were individually
recited herein. All methods described herein can be performed in
any suitable order unless otherwise indicated herein or otherwise
clearly contradicted by context. The use of any and all examples,
or exemplary language (e.g., "such as") provided herein, is
intended merely to better illuminate the claimed apparatus, device,
system, or method and does not impose a scope limitation unless
otherwise claimed. No language in the specification should be
construed as indicating any non-claimed element as essential to the
practice of the claimed apparatus, device, system, or method.
[0037] Preferred embodiments of the claimed apparatus, device,
system, or method are described herein, including the best mode
known to the inventors for practicing the claimed apparatus,
device, system, or method. It should be understood that the
illustrated embodiments are exemplary only, and should not be taken
as limiting the scope of the claimed apparatus, device, system, or
method.
* * * * *