U.S. patent application number 13/430617 was filed with the patent office on 2013-05-09 for heat-dissipating device and heat-dissipating system.
This patent application is currently assigned to INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE. The applicant listed for this patent is Kuo-Hsiang Chien, Chi-Chuan Wang, Kai-Shing Yang. Invention is credited to Kuo-Hsiang Chien, Chi-Chuan Wang, Kai-Shing Yang.
Application Number | 20130112377 13/430617 |
Document ID | / |
Family ID | 48208614 |
Filed Date | 2013-05-09 |
United States Patent
Application |
20130112377 |
Kind Code |
A1 |
Yang; Kai-Shing ; et
al. |
May 9, 2013 |
HEAT-DISSIPATING DEVICE AND HEAT-DISSIPATING SYSTEM
Abstract
A heat-dissipating device and a heat-dissipating system are
provided. The heat-dissipating system includes a driver, a
heat-exchanger and a heat-dissipating device. The heat-exchanger is
communicated to the driver and includes a body, a hydrophobic
membrane and a cover. The body has an inlet, an outlet and a
channel. Both ends of the channel exposed on a body's surface are
respectively communicated to the inlet and the outlet, the inlet
and outlet are communicated respectively to the driver and
heat-exchanger. The membrane is disposed on the body's surface and
covers the channel. The cover combines with the body and has a
chamber and an exhaust port. The membrane separates the channel
from the chamber communicated to the exhaust port communicated to
the heat-exchanger. The driver drives a working fluid to the
heat-dissipating device, and the fluid further goes to the
heat-exchanger from the heat-dissipating device and then back to
the driver.
Inventors: |
Yang; Kai-Shing; (Changhua
County, TW) ; Wang; Chi-Chuan; (Hsinchu County,
TW) ; Chien; Kuo-Hsiang; (Hsinchu County,
TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Yang; Kai-Shing
Wang; Chi-Chuan
Chien; Kuo-Hsiang |
Changhua County
Hsinchu County
Hsinchu County |
|
TW
TW
TW |
|
|
Assignee: |
INDUSTRIAL TECHNOLOGY RESEARCH
INSTITUTE
Hsinchu
TW
|
Family ID: |
48208614 |
Appl. No.: |
13/430617 |
Filed: |
March 26, 2012 |
Current U.S.
Class: |
165/120 ;
165/121; 165/181 |
Current CPC
Class: |
H01L 2924/0002 20130101;
H01L 23/427 20130101; H05K 7/20263 20130101; H01L 2924/0002
20130101; H01L 2924/00 20130101 |
Class at
Publication: |
165/120 ;
165/181; 165/121 |
International
Class: |
F28F 1/10 20060101
F28F001/10; F28F 13/12 20060101 F28F013/12 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 8, 2011 |
TW |
100140698 |
Claims
1. A heat-dissipating device, comprising: a body, having an inlet,
an outlet and a channel, wherein both ends of the channel are
respectively communicated to the inlet and the outlet, and the
channel is exposed on a surface of the body; a hydrophobic
membrane, disposed on a surface of the body and covering the
channel; and a cover, combining with the body and having a chamber
and an exhaust port, wherein the hydrophobic membrane separates the
channel from the chamber, and the chamber is communicated to the
exhaust port.
2. The heat-dissipating device as claimed in claim 1, further
comprising a supporting plate disposed between the body and the
cover and fixing the hydrophobic membrane onto the surface of the
body, wherein the supporting plate has a plurality of ventilation
ports.
3. The heat-dissipating device as claimed in claim 1, wherein a
contact angle between the hydrophobic membrane and a working fluid
in the channel is between 90.degree. and 180.degree..
4. The heat-dissipating device as claimed in claim 1, wherein the
channel is a continuous S-shape.
5. The heat-dissipating device as claimed in claim 1, wherein the
channel branches in multiple times from both the inlet and the
outlet to the middle.
6. The heat-dissipating device as claimed in claim 1, wherein the
channel comprises a plurality of parallel branches.
7. A heat-dissipating system, comprising: a driver; a
heat-exchanger, communicated to the driver; a heat-dissipating
device, comprising: a body, having an inlet, an outlet and a
channel, wherein both ends of the channel are respectively
communicated to the inlet and the outlet, the channel is exposed on
a surface of the body, the inlet is communicated to the driver and
the outlet is communicated to the heat-exchanger; a hydrophobic
membrane, disposed on the surface of the body and covering the
channel; and a cover, combining with the body and having a chamber
and an exhaust port, wherein the hydrophobic membrane separates the
channel from the chamber, the chamber is communicated to the
exhaust port, the exhaust port is communicated to the
heat-exchanger, the driver is for driving a working fluid to the
heat-dissipating device and the working fluid further goes to the
heat-exchanger from the heat-dissipating device and then back to
the driver.
8. The heat-dissipating system as claimed in claim 7, wherein the
heat-dissipating device further comprises a supporting plate
disposed between the body and the cover and fixing the hydrophobic
membrane onto the surface of the body, the supporting plate has a
plurality of ventilation ports.
9. The heat-dissipating system as claimed in claim 7, wherein a
contact angle between the hydrophobic membrane and the working
fluid in the channel is between 90.degree. and 180.degree..
10. The heat-dissipating system as claimed in claim 7, wherein the
channel is a continuous S-shape.
11. The heat-dissipating system as claimed in claim 7, wherein the
channel branches in multiple times from both the inlet and the
outlet to the middle.
12. The heat-dissipating system as claimed in claim 7, wherein the
channel comprises a plurality of parallel branches.
13. The heat-dissipating system as claimed in claim 7, further
comprising a filter disposed between the driver and the inlet.
14. The heat-dissipating system as claimed in claim 7, further
comprising a one-way valve disposed between the exhaust port and
the heat-exchanger.
15. The heat-dissipating system as claimed in claim 7, further
comprising a reservoir disposed between the heat-exchanger and the
driver for storing the working fluid.
16. The heat-dissipating system as claimed in claim 7, wherein the
heat-exchanger has a fan.
17. The heat-dissipating system as claimed in claim 7, wherein the
driver is a pump.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority benefit of Taiwan
application serial no. 100140698, filed on Nov. 8, 2011. The
entirety of the above-mentioned patent application is hereby
incorporated by reference herein and made a part of this
specification.
BACKGROUND
[0002] 1. Technical Field
[0003] The disclosure generally relates to a heat-dissipating
device and a heat-dissipating system, and more particularly, to a
heat-dissipating device and a heat-dissipating system able to
separate gas and liquid apart.
[0004] 2. Related Art
[0005] Looking at Taiwan's past, present and future development of
key industries, no matter the semiconductor industry which
long-term led the economic development in Taiwan, or the green
energy and energy-saving products which are widely valued by the
world due to global warming, soaring oil prices and other factors,
such as LED application products (road lamps, vehicle lights,
indoor lighting and so on) and high efficiency solar cells, and or
the potentially prosperous key industries in future such as cloud
computing products, all the products face a challenge of the
internally-produced heat. The heat is uneasily to be removed so
that the efficiency, the stability and the lifetime of the products
are affected and further, the developments of the above-mentioned
products and the relevant industries are limited. For the relevant
products, the causes to produce high temperature can be divided
into two categories, namely, high caloric amount and concentrated
heat-source (high heat-density). The influence of the high caloric
amount can be explained by using a computer system as an example.
Along with the evolution of the IC (integrated circuit) packaging
technology and the industrial processes in the development of
electronic components, the internal IC packaging density and the
operation speed thereof are rapidly increased. However, the
high-speed operation frequency and the continuously-reduced circuit
line width would make the caloric amount of the electronic
components relatively advanced. The statistics has shown that 55%
cases of the electronic product's damage are caused by too-high
temperature and reducing the temperature of a chip every 10.degree.
C. can increase the computing efficiency by 1%-3%, which indicates
a significant influence of temperature on the performance, the
lifetime and the stability of the related electronic equipments. In
this regard, the effective thermal design enables high reliability,
great stability and long lifetime for the electronic components and
equipments and further overcomes the limitation for developing the
high-speed chips.
[0006] The real heat-dissipating change sourced from the high
heat-density rests in the presence of extreme-high hot spots where
the spreading resistance strongly affects the integrated
performance of a heat-dissipating module. In addition, in order to
increase the light flux, high-power LEDs (light-emitting diodes)
are often packaged in array module mode. These light-emitting chips
with high-density arrangement further make the heat-dissipating
design more difficult. Most of the early cooling of electronic
components adopts a natural convection way or a forced convection
air-cooling way, where the heat exchange between the heat sink made
of copper or aluminum and the electronic components in association
with a fan or a heat pipe are used to dissipate heat to outside.
Such measure has simpler structure and low cost, but the
heat-transferring effect is poor and the issue related to noise is
not solved, so that the conventional early measures can not meet
the requirement of products with high caloric amount. Therefore,
various more effective electronic heat-dissipating means such as
thermal electric chips, liquid-cooling method and vapour
compression refrigeration and air-conditioning systems have been
gradually developed and got applications. Among them, the
thermoelectric cooler has a higher cost and the commercial
thermoelectric cooler has relatively low efficiency, both which
need to input additional energy to cool the heat-source. Although
vapour compression cooling system can achieve a lower cooling
temperature and can effectively expel the waste-heat of the
electronic chip, but such a low-temperature environment is not
suitable for electronic components, because when the refrigerant's
evaporation temperature is lower than the dew point temperature,
condensation phenomenon occurs, and the condensation water vapour
will have adverse effects on electronic components and result in
component damage and failure, and the products are too
expensive.
[0007] Currently, the common liquid cooling mean available on the
market is an effective way for cooling a system, and in general,
they mostly use water as the working fluid and a single-phase
liquid mode for operation. In addition, to enhance the cooling
capacity of liquid cooling systems, it is often realized by
narrowing flowing-channel diameter of the cold plate. Under the
high caloric amount situation, micro-channel has superior heat
dissipation effect, but the relatively narrow scale of the
flowing-channel also requires the pump can provide a very high
thrust to drive the working fluid. Meanwhile, the working fluid
passing the high temperature area would generate bubbles, which
further clogs the flowing-channel, resulting in higher thrust need
for the pump to provide. As a result, the liquid cooling scheme has
a lower feasibility.
SUMMARY
[0008] The disclosure is directed to a heat-dissipating device able
to solve the problem of clogging the channels by bubbles.
[0009] The disclosure is directed to a heat-dissipating system able
to solve the problem of requiring a high thrust to drive the
working fluid in the channels.
[0010] The heat-dissipating device of the disclosure includes a
body, a hydrophobic membrane and a cover. Both ends of the channel
are respectively communicated to the inlet and the outlet, and the
channel is exposed on a surface of the body. The hydrophobic
membrane is disposed on the surface of the body and covers the
channel. The cover combines with the body and has a chamber and an
exhaust port, in which the hydrophobic membrane separates the
channel from the chamber. The chamber is communicated to the
exhaust port.
[0011] The heat-dissipating system of the disclosure includes a
driver, a heat-exchanger and a heat-dissipating device. The
heat-exchanger is communicated to the driver. The heat-dissipating
device includes a body, a hydrophobic membrane and a cover. The
body has an inlet, an outlet and a channel, in which both ends of
the channel are respectively communicated to the inlet and the
outlet, the channel is exposed on a surface of the body, the inlet
is communicated to the driver and the outlet is communicated to the
heat-exchanger. The hydrophobic membrane is disposed on the surface
of the body and covers the channel. The cover combines with the
body and has a chamber and an exhaust port, in which the
hydrophobic membrane separates the channel from the chamber, the
chamber is communicated to the exhaust port, the exhaust port is
communicated to the heat-exchanger, the driver is for driving a
working fluid to the heat-dissipating device and the working fluid
further goes to the heat-exchanger from the heat-dissipating device
and then back to the driver.
[0012] Based on the description above, in the heat-dissipating
device and the heat-dissipating system of the disclosure, a
hydrophobic membrane is utilized to effectively separate liquid and
gas apart, which further ensure smoothly pushing the working fluid
to keep a high heat-dissipating efficiency.
[0013] Several exemplary embodiments accompanied with figures are
described in detail below to further describe the disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The accompanying drawings are included to provide further
understanding, and are incorporated in and constitute a part of
this specification. The drawings illustrate exemplary embodiments
and, together with the description, serve to explain the principles
of the disclosure.
[0015] FIG. 1 is a schematic diagram of a heat-dissipating system
according to an embodiment of the disclosure.
[0016] FIG. 2 is an exploded diagram of the heat-dissipating device
of FIG. 1.
[0017] FIGS. 3 and 4 are schematic diagrams showing channels of
other two embodiments.
[0018] FIG. 5 includes four photos continuously high-speed captured
showing expelled bubbles during conducting heat-dissipating
experiments.
[0019] FIG. 6 shows the contact angle.
DETAILED DESCRIPTION OF DISCLOSED EMBODIMENTS
[0020] FIG. 1 is a schematic diagram of a heat-dissipating system
according to an embodiment of the disclosure and FIG. 2 is an
exploded diagram of the heat-dissipating device of FIG. 1.
Referring to FIGS. 1 and 2, a heat-dissipating system 100 of the
embodiment includes a driver 110, a heat-exchanger 120 and a
heat-dissipating device 200. The heat-exchanger 120 is communicated
to the driver 110. In more details, a working fluid 50 flows from
the driver 110 to the heat-dissipating device 200. After the
working fluid 50 takes heat away from the heat-dissipating device
200 to get warmed, the working fluid 50 flows to the heat-exchanger
120 to conduct heat-exchanging with the ambient environment.
Thereafter, the working fluid 50 flows back to the driver 110 from
the heat-exchanger 120 so as to complete one cycle. The
heat-dissipating system 100 of the embodiment is, for example, the
one to form closed cycle.
[0021] The heat-dissipating device 200 includes a body 210, a
hydrophobic membrane 220 and a cover 230. The body 210 has an inlet
212, an outlet 214 and a channel 216. Both ends of the channel 216
are respectively communicated to an inlet 212 and an outlet 214.
The channel 216 is exposed on the surface of the body 210. In other
words, if solely observing the body 210, the bottom of the channel
216 can be directly seen from the surface of the body 210 where no
any other structures cover the channel 216. The inlet 212 is
communicated to the driver 110 and the outlet 214 is communicated
to the heat-exchanger 120. The working fluid 50 enters the channel
216 from the driver 110 via the inlet 212, and then, enters the
heat-exchanger 120 from the channel 216 via the outlet 214. The
hydrophobic membrane 220 is disposed on the surface of the body 210
and covers the channel 216. The hydrophobicity of the hydrophobic
membrane 220 makes the working fluid 50 unable to pass through the
hydrophobic membrane 220, but gas can pass through the hydrophobic
membrane 220.
[0022] The cover 230 is combined with the body 210 and has a
chamber 232 and an exhaust port 234. The hydrophobic membrane 220
separates the channel 216 from a chamber 232, while the chamber 232
is communicated to the exhaust port 234. The exhaust port 234 is
communicated to the heat-exchanger 120. The body 210 is configured
for contacting a heat-source 60, which can be, for example, an LED,
a chip, a solar energy or other components requiring
heat-dissipating. The heat of the heat-source 60 is transferred to
the surface of the body 210, and then, to the working fluid 50 in
the channel 216. During the working fluid 50 is being warmed, the
heat is brought away from the body 210 to achieve heat-dissipating
purpose. The working fluid 50 can be even converted from liquid
state to vapour state, and during the liquid-vapour conversion,
more heat would be brought away. In addition, the working fluid 50
in vapour state after the conversion can quickly pass through the
hydrophobic membrane 220 to enter the chamber 232 and flow to the
heat-exchanger 120 from the exhaust port 234. In this way, it can
avoid the working fluid 50 in vapour state in the channel 216 from
forming bubbles to block the flowing of the working fluid 50, which
ensure the working fluid 50 smoothly and ceaselessly cycling and
bringing away heat to get the optimum heat-dissipating efficiency.
The working fluid in vapour state 50 after cooling would be
converted back to liquid state again.
[0023] The driver 110 is configured for providing a driving force
to drive the working fluid 50 to the heat-dissipating device 200.
Then, the working fluid 50 flows to the heat-exchanger 120 from the
heat-dissipating device 200 and back to the driver 110.
[0024] The heat-dissipating device 200 of the embodiment further
includes a supporting plate 240 disposed between the body 210 and
the cover 230 and the supporting plate 240 fixes the hydrophobic
membrane 220 on the surface of the body 210. The supporting plate
240 has a plurality of ventilation ports 242. The working fluid in
vapour state 50 can quickly pass through the hydrophobic membrane
220 and the ventilation ports 242 to enter the chamber 232. The
major function of the supporting plate 240 is for avoiding the
hydrophobic membrane 220 from being peeled off from the surface of
the body 210 and thereby avoiding the working fluid in liquid state
50 from entering the chamber 232. However, if the hydrophobic
membrane 220 were appropriately fixed, the supporting plate 240 can
be saved.
[0025] The hydrophobicity of the hydrophobic membrane 220 in the
embodiment is explained in more details as follows. The contact
angle .theta. between the hydrophobic membrane 220 and the working
fluid 50 in the channel 216 is between 90.degree. and 180.degree..
Referring to FIG. 6, it shows the contact angle. The contact angle
.theta. is the angle formed at the contact interface of the solid
surface and liquid/gas. As shown in FIG. 6, the contact angle
.theta. is a system formed by the interaction of three different
interfaces. In general, the contact angle .theta. plays a
constraint for a shape of a droplet defined from Young-Laplace
equation, wherein the droplet is on an unit of lateral solid
surface. The measurement of contact angle .theta. can be finished
by a contact angle protractor. The contact angle .theta. is not
limited to the liquid/gas interface, it is applicable to interface
between two liquid or between two vapor. Generally speaking, if a
droplet on a solid surface strongly forced by force of the solid
surface (such as water and a strongly hydrophilic surface of a
solid), the droplet will be completely flatly attached to the
surface of the solid, and the contact angle .theta. is about
0.degree.. With non-hydrophilic solid, the contact angle .theta. is
larger, to about 90.degree.. In many highly hydrophilic surfaces,
contact angle .theta. of water droplet is about 0.degree. to
30.degree.. If the surface of a solid is hydrophobic, the contact
angle .theta. is larger than 90.degree.. For the high hydrophobic
surface, the contact angle .theta. of water droplet can be as high
as 150.degree. or even 180.degree.. On this surface, the water
droplets only stay on, not really infiltrate to the surface. It is
to be called super-hydrophobic. We can observe it on the
appropriate fluoride treated (Teflon coating) surface, and it can
be called the lotus effect. This super hydrophobic phenomenon on
the surface of new material bases on the same principle as the
principle founded on the lotus leaf surface (leaf with many small
protrusions), and even honey has a super hydrophobic phenomenon on
the surface of the new material. The contact angle .theta. provide
information of force between the surface and the liquid. But
sometimes, the contact angle .theta. may not refer to the angle
from the interface between liquid/gas to the liquid, but refers to
the angle from the interface between liquid/gas to the gas. The
above interpreted angles are complementary angles. The channel 216
of the embodiment is a continuous S-shape. FIGS. 3 and 4 are
schematic diagrams showing channels of other two embodiments. In
the embodiment of FIG. 3, the channel 316 branches in multiple
times from the inlet 312 to the outlet 314. The channel 316
repeatedly branches from the inlet 312 and reaches the middle
position, and then the multiple branches merge one by one and
converge finally at the outlet 314. In the embodiment of FIG. 4,
the channel 416 includes a plurality of parallel branches.
[0026] FIG. 5 includes four real photos continuously high-speed
captured showing expelled bubbles during conducting
heat-dissipating experiments based on the channel of FIG. 4. It is
obvious from FIG. 5 that the area R10 is almost occupied by bubbles
(marked with oblique lines) at the beginning (0 sec.), but the area
occupied by the bubbles is noticeably shrunk after 0.04 sec. and
after 0.08 sec. Further, after 0.12 sec. the area R10 occupied by
the bubbles is shrunk roughly to a half. It can be seen the
heat-dissipating device of the disclosure is certainly helpful to
quickly expel the gas from the channel via the hydrophobic
membrane.
[0027] Referring to FIG. 1 again, the heat-dissipating system 100
of the embodiment can further include a filter 130 disposed between
the driver 110 and the inlet 212. The filter 130 is configured for
filtering possible impurities in the working fluid 50. The
heat-dissipating system 100 of the embodiment can further include a
one-way valve 140 disposed between the exhaust port 234 and the
heat-exchanger 120. The one-way valve 140 can avoid the working
fluid in liquid/vapour state 50 from being refluxed to enter the
chamber 232. The heat-dissipating system 100 of the embodiment
further includes a reservoir 150 disposed between the
heat-exchanger 120 and the driver 110 for storing the working fluid
50 and thereby to adjust the amount of the working fluid 50 flowing
cyclically in the whole system. The heat-exchanger 120 of the
embodiment has a fan 122 to advance the efficiency of the
heat-exchanging between the heat-exchanger 120 and the ambient
environment so as to quickly cool the working fluid 50. The driver
110 of the embodiment is a pump, but other fauns of driver are
allowed.
[0028] In summary, in the heat-dissipating device and the
heat-dissipating system of the disclosure, a hydrophobic membrane
is utilized to quickly expel gas from the channel to the chamber so
as to reduce the probability of that the clogged channel by bubbles
makes the working fluid unable to smoothly flow, which further
ensure the working fluid ceaselessly getting cycles to keep a high
heat-dissipating efficiency.
[0029] It will be apparent to those skilled in the art that various
modifications and variations can be made to the structure of the
disclosed embodiments without departing from the scope or spirit of
the disclosure. In view of the foregoing, it is intended that the
disclosure cover modifications and variations of this disclosure
provided they fall within the scope of the following claims and
their equivalents.
* * * * *