US20120097368A1

US20120097368A1 - Heating exchange chamber for liquid state cooling fluid

Info

Publication number: US20120097368A1
Application number: US13/030,614
Authority: US
Inventors: Chien-An Chen; Yi-Ling Chen
Original assignee: Inventec Corp
Current assignee: Inventec Corp
Priority date: 2010-10-26
Filing date: 2011-02-18
Publication date: 2012-04-26
Also published as: TWI407898B; TW201218932A

Abstract

A heat exchange chamber for liquid state cooling fluid is provided, which comprises a casing and a thermal dissipation device, the casing has a cavity and the thermal dissipation device is sited in the cavity. A cooling fluid flows through the cavity along a flow direction. The cross-sectional area of the cavity whose direction is perpendicular to the flow direction shows linear increase or non-linear increase gradually along the flow direction, and a part of the cooling fluid vaporizes after flowing through the thermal dissipation device. The chamber along the flow direction shows different pressures, and two phase fluid flows automatically due to the pressure difference. The heat exchange chamber for liquid state cooling fluid could lighten the loading of the pump which is for circulating the cooling fluid, and it also achieve the efficacy of saving energy and raising efficiency.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims benefits and priority under 35 U.S.C. §119(a) on Patent Application No. 099136464 filed in Taiwan, R.O.C. on Oct. 26, 2010, the entire contents of which are hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to a heat dissipation module using cooling fluid, and more particularly, to a chamber whose cross section is increasing gradually in a flowing direction of a two-phase fluid inside the chamber so as to enable the two-phase fluid to be forced to flow through the chamber automatically by the pressure difference resulting from the chamber of increasing cross section.

BACKGROUND OF THE INVENTION

In many typical mainframe computers such as servers, poor heat dissipation performance is usually the case that cause the computer to malfunction so that how to design a heat sink or heat dissipating device with optimized heat dissipation performance is becoming the key issue in modern electronic computing industry. IN addition, taking the power consumed by servers of any common data center for instance, the power used by the heat dissipation system for maintaining the operation of such servers is also twice as much. And not to mention that the complexity of the heat dissipation system for modern cloud data centers that are crowded with servers in high density is generally almost double comparing with those for common data centers. That is, in the enclosed space of a server room of a cloud data center, the heat that all those boxes generate can quickly increase the ambient temperature beyond equipment specifications. The results can be ugly if there is no proper heat dissipation system with good performance available and consequently all distinct possibilities can be caused, such as the operation of the servers may be unstable or even fail, energy can be wasted, the performance of the personnel working in the server room may be poor since an uncomfortable working environment can be resulted, the cost for managing the server room may increase, and so on.
Among those many conventional apparatus for heat dissipation, the heat exchange chamber for liquid state cooling fluid is the one that is commonly seen and used for allowing a cooling fluid to flow therein while enabling a heat exchanging process to be performed between the cooling fluid and a heat source, and thus reducing the temperature of the heat source. During the heat exchanging process, a portion of such liquid state cooling fluid flowing in the heat exchange chamber will be vaporized by the heat absorbed thereby, and since the bubbles resulting from the vaporized cooling fluid will massively accumulated inside the heat exchange chamber, the flowing of the cooling fluid inside the heat exchange chamber can be blocked or even clogged and thus the heat dissipation performance of the heat exchange chamber is adversely affected. Consequently, for many heat exchange chambers housed inside the server's casing, they are generally being configured with additional pumps for pressurizing the cooling fluid to flow smoothly inside the heat exchange chamber, and thus ensuring the circulating of the cooling fluid for heat dissipation. Nevertheless, since there can be plenty of such heat exchange chambers for one server, the power consumption relating to those pumps used for ensuring the flow circulation of those heat exchange chambers can be huge and considered to be wasteful.
Therefore, it is in need of a heat exchange chamber for liquid state cooling fluid that can ensure the cooling fluid to flow smoothly while alleviating the load of the pump used for pressuring the flow of the cooling fluid inside the heat exchange chamber.

SUMMARY OF THE INVENTION

In view of the disadvantages of prior art, the primary object of the present invention is to provide a chamber whose cross section is increasing gradually in a flowing direction of a two-phase fluid inside the chamber so as to enable the two-phase fluid to be forced to flow through the chamber automatically by the pressure difference resulting from the chamber of increasing cross section.
To achieve the above object, the present invention provides a heat exchange chamber for liquid state cooling fluid, which comprises: a casing, configured with a cavity, an inlet and an outlet in a manner that the inlet is provided for allowing a cooling fluid to flow into the cavity and the outlet is provided for allowing the cooling fluid to flow out of the cavity as the cooling fluid is enabled to flow in a flowing direction through of the cavity; and a thermal dissipation device, disposed inside the cavity for allowing a portion of the cooling fluid to flow therethrough so as to be vaporized; wherein the diameter of the outlet is larger than that of the inlet; and the cross-sectional area of the cavity that is perpendicular to the flowing direction is increasing gradually along the flowing direction in a manner selected from the group consisting of: a linear manner and a non-linear manner. In an embodiment of the invention, the casing further comprises: a base, being provided for engaging with a heat source while being arranged in thermal contact with the thermal dissipation device. Moreover, the thermal dissipation device, being constructed smaller than the cavity in profile, is comprised of a plurality of heat dissipating fins while enabling each heat dissipating fin to be disposed parallel with the flowing direction; and the portion of the cavity that is not occupied by the thermal dissipation device forms an accommodation space to be provided for the vaporized cooling fluid to accumulate thereat, and the accommodation space is constructed in communication with either only a portion of the outlet or all the outlet.
In an exemplary embodiment of the invention, the cross-sectional area of the accommodation space that is perpendicular to the flowing direction is increasing gradually along the flowing direction in a manner selected from the group consisting of: a linear manner and a non-linear manner. In addition, as a portion of the cooling fluid is vaporized while flowing through the thermal dissipation device, pressure differences will be resulted along the flowing direction inside the accommodation space of increasing cross section. In another exemplary embodiment of the invention, the height of each heat dissipating fin is tapering along the flowing direction for enabling the cross-sectional area of the accommodation space to increase gradually.
Further scope of applicability of the present application will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention and wherein:

FIG. 1 is a schematic diagram showing a heat exchange chamber for liquid state cooling fluid according to a first embodiment of the invention.

FIG. 2 is a schematic diagram showing a heat exchange chamber for liquid state cooling fluid with a cavity constructed different from the one shown in the first embodiment of the invention.

FIG. 3 is a schematic diagram showing a heat exchange chamber for liquid state cooling fluid according to a second embodiment of the invention.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

For your esteemed members of reviewing committee to further understand and recognize the fulfilled functions and structural characteristics of the invention, several exemplary embodiments cooperating with detailed description are presented as the follows.
Please refer to FIG. 1 and FIG. 2, which are a schematic diagram showing a heat exchange chamber for liquid state cooling fluid according to a first embodiment of the invention, and a schematic diagram showing a heat exchange chamber for liquid state cooling fluid with a cavity constructed different from the one shown in the first embodiment. As shown in FIG. 1, the heat exchange chamber comprises: a casing 1 and a thermal dissipation device 2. The casing 1 is configured with a cavity 10, an inlet 11 and an outlet 12 in a manner that the inlet 11 is provided for allowing a cooling fluid 0 to flow into the cavity 10 and the outlet 12 is provided for allowing the cooling fluid 0 to flow out of the cavity 10 as the cooling fluid is enabled to flow in a flowing direction, as the arrow 00 shown in FIG. 1. In this embodiment, the diameter of the outlet 12 is larger than that of the inlet 11, by that the cavity 10 can be prevented from having too much gas being accumulated therein, and thus the boiling point of the cooling fluid 0 can be prevented from being raised with the increasing of the pressure inside the cavity 10 caused by the gas accumulation, so that the heat dissipating efficacy of the cooling fluid is prevented from reducing. As shown in FIG. 1, the cooling fluid 0 is enabled to flow through the cavity 10 in the flowing direction 00, and the cross-sectional area of the cavity 10 that is perpendicular to the flowing direction is constructed increasing gradually along the flowing direction 00 in a manner selected from the group consisting of: a linear manner and a non-linear manner. The thermal dissipation device 2 is received inside the cavity 10, by which a portion of the cooling fluid 0 flowing therethrough is vaporized into a plurality of bubbles that will mix with the cooling fluid 0 that is not vaporized so as to form a two-phase cooling fluid. Moreover, as the cross-sectional area of the cavity 10 that is perpendicular to the flowing direction is constructed varying gradually along the flowing direction 00, pressure differences will be caused inside the cavity 10 along the flowing direction 00. In detail, by constructing the cavity 10 with increasing cross section in the flowing direction 00, pressure difference will be caused in a manner that the closer to the outlet 12, the smaller the pressure will be induced, that can be used for inducing the two-phase cooling fluid to flow automatically in the flowing direction.
In this embodiment, the casing 1 further comprises: a base 13, being provided for engaging with a heat source 3, by that the heat emitted from the heat source can be transmitted to the heat exchange chamber through the base 13. It is noted that the heat source 3 can be a center processing unit or a chip module, but is not limited thereby. In addition, the base 13 is also being arranged in thermal contact with the thermal dissipation device 2 so as to transmit heat thereto. As shown in FIG. 1, the thermal dissipation device 2 further comprises a plurality of heat dissipating fins 20, whereas the surface area of each heat dissipating fin 20 is constructed larger than that of the heat source 3 so as to facilitate the heat exchanging therebetween. Moreover, each of the plural heat dissipating fins 20 is disposed in a direction parallel with the flowing direction 00 while forming narrow channels between any two neighboring heat dissipating fins 20 that are consequently arranged parallel with the flowing direction 00. Accordingly, when a portion of the cooling fluid 0 flows through the plural channels sandwiched between the plural heat dissipating fins 20, the heat dissipated from the heat dissipating fins 20 will be absorbed thereby so that the portion of the cooling fluid 0 is vaporized. In detail, by the disposition of the thermal dissipation device 2 inside the cavity 10, the portion of the cavity 10 that is not occupied by the thermal dissipation device 2 will form an accommodation space 100, which is provided for the vaporized cooling fluid 0 to accumulate thereat as the vaporized cooling fluid 0 will move naturally upward to the accommodation space 100. Since the cross section area of the cavity 10 is increasing along with the flowing direction, the cross section area of the accommodation space 100 is increasing as wells so that pressure differences will be caused inside the accommodation space 100 along the flowing direction. Moreover, the accommodation space 100 is constructed either in communication with a portion of the outlet 12, or in communication with all the outlet 12, not only the vaporized cooling fluid 0 is able to flow smoothly out of the cavity 10 through the outlet 12, but also the cooling fluid 0 that is not vaporized can flow smoothly in the flowing direction out of the cavity 10 through the outlet 12.
There can be various configurations for forming cavity 10 in a heat exchange chamber with its cross section to increase in a flowing direction, as the two disclosed in FIG. 1 and FIG. 2. In the configuration shown in FIG. 1, the extensions of the top panel and the base 13 of the casing 1 will intersect each other, forming a line, while the distance measured between the line and the inlet 11 to be smaller than the distance measured between the line and the outlet 12. That is, the top panel is not arranged parallel with the base 13 in a manner that either the top panel is inclinedly arranged by an angle with respect to the water level, or the base 13 is inclinedly arranged by an angle with respect to the water level, or even both of the top panel and the base 13 are respectively inclinedly arranged by an angle with respect to the water level. Nevertheless, in a condition that the top panel is not arranged parallel with the base 13 and simultaneously the distance between the top panel and the base 13 is increasing in the flowing direction, the cross-sectional area of the cavity 10 is increasing gradually along the flowing direction 00. In the embodiment shown in FIG. 1, since the top panel is substantially a ramp, the cross-sectional area of the cavity is increasing along the flowing direction in a linear manner. On the other hand, although in the configuration shown in FIG. 2 that the top panel and the base 13 are arrange parallel with each other, the cross-sectional area of the cavity 10 can still be increasing gradually along the flowing direction 00 by either enabling the thickness of the base 13 to be reduced along the flowing direction, or enabling the thickness of the top panel to be reduced along the flowing direction. Nevertheless, there can be other method for causing the cross-sectional area of the cavity 10 can still be increasing gradually along the flowing direction 00 that it is not limited by the aforesaid methods.
It is noted that by constructing a stair-like surface on either the top panel of FIG. 1 or the base 13 of FIG. 2, to be used for replacing the ramped surfaces shown in those two embodiments, the cross-sectional area of the cavity 10 can still be constructed increasing gradually along the flowing direction 00, but in a non-linear manner.
Moreover, the inlet 11 of the casing 1 can be shaped as a circle or an oval. But in this embodiment, the inlet 11 is shaped like a square. Correspondingly, for enabling the cooling fluid 0 to contact with the thermal dissipation device 2 uniformly after flowing into the cavity 10 through the inlet 11, there is a block 14 being disposed inside the cavity 10 at a position proximate to the inlet 11. In this embodiment, the flow resisting portion 14 is substantially a block hanging on the top panel of the casing 1, by that a neck is formed inside the cavity 10 at the position proximate to the inlet 11. Accordingly, as soon as the cooling fluid 0 flows through the neck, it is forced to distribute uniformly and flows into a plurality of channels formed between the plural heat dissipating fins 20 of the thermal dissipation device 2. Thus, by the disposition of the flow resisting portion 14, the heat dissipating effect of the thermal dissipation device 2 can be ensured as the cooling fluid 0 is distributed uniformly with respect to the plural heat dissipating fins 20 while preventing the same from being concentrated to the center channel of the plural channels. It is noted that the flow resisting portion 14 can be formed in various manner that it is not limited by the aforesaid embodiment.
Please refer to FIG. 3, which is a schematic diagram showing a heat exchange chamber for liquid state cooling fluid according to a second embodiment of the invention. As shown in FIG. 3, the heat exchange chamber comprises: a casing 1 and a thermal dissipation device 2. The casing 1 is configured with a cavity 10, an inlet 11 and an outlet 12 in a manner that the inlet 11 is provided for allowing a cooling fluid 0 to flow into the cavity 10 and the outlet 12 is provided for allowing the cooling fluid 0 to flow out of the cavity 10. In this embodiment, the diameter of the outlet 12 is larger than that of the inlet 11, by that the cavity 10 can be prevented from having too much gas being accumulated therein, and thus the boiling point of the cooling fluid 0 can be prevented form increasing with the increasing of the pressure inside the cavity 10 caused by the gas accumulation, so that the heat dissipating efficacy of the cooling fluid is prevented from reducing. As shown in FIG. 3, the cavity 10 has an accommodation space 100 formed therein while enabling the thermal dissipation device 2 to be disposed inside the cavity occupying the remaining space therein other than the accommodation space 100, as the cooling fluid 0 is enabled to flow through the cavity 10 in a flowing direction 00. Similarly, the cross-sectional area of the accommodation space 100 that is perpendicular to the flowing direction is constructed increasing gradually along the flowing direction 00 in a manner selected from the group consisting of: a linear manner and a non-linear manner, so as to cause pressure differences along the flowing direction 00 inside the accommodation space 100. Moreover, as a portion of the cooling fluid 0 flowing through the thermal dissipation device 2 is vaporized, forming a two-phase fluid, and as the cross-sectional area of the accommodation space 100 that is perpendicular to the flowing direction is constructed varying gradually along the flowing direction 00, pressure differences will be caused inside the accommodation space 100 along the flowing direction 00. In detail, by constructing the accommodation space 100 with increasing cross section in the flowing direction 00, pressure difference will be caused in a manner that the closer to the outlet 12, the smaller the pressure will be induced, that can be used for inducing the two-phase cooling fluid to flow automatically in the flowing direction 00. As shown in FIG. 3, the difference between this embodiment and the prior embodiments is that: the configurations for forming an accommodation spaced 100 with its cross section to increase along with the flowing direction 00 is achieved by enabling the height of each heat dissipating fin 20 to taper along the flowing direction 00.
To sum up, by the configuration of a cavity with increasing cross section for inducing pressure differences inside the cavity, the heat exchange chamber of the invention can ensure a two-phase cooling fluid to flow smoothly and automatically through the cavity. Thus, the heat exchange chamber can perform well without the help of any additional pumps for pressurizing the cooling fluid to flow inside the heat exchange chamber, so that the heat exchange chamber for liquid state cooling fluid not only can lighten the loading of the pump which is used for circulating the cooling fluid, but also can achieve the efficacy of saving energy and raising efficiency.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.

Claims

1. A heat exchange chamber for liquid state cooling fluid, comprising:

a casing, configured with a cavity, an inlet and an outlet in a manner that the inlet is provided for allowing a cooling fluid to flow into the cavity and the outlet is provided for allowing the cooling fluid to flow out of the cavity as the cooling fluid is enabled to flow in a flowing direction through of the cavity; and

a thermal dissipation device, disposed inside the cavity for allowing a portion of the cooling fluid to flow therethrough so as to be vaporized;

wherein, the cross-sectional area of the cavity that is perpendicular to the flowing direction is constructed increasing gradually along the flowing direction in a manner selected from the group consisting of: a linear manner and a non-linear manner, so as to cause pressure differences along the flowing direction inside the cavity.

2. The heat exchange chamber of claim 1, wherein the casing further comprises: a base, being provided for engaging with a heat source while being arranged in thermal contact with the thermal dissipation device.

3. The heat exchange chamber of claim 1, wherein the thermal dissipation device is constructed smaller than the cavity in profile.

4. The heat exchange chamber of claim 1, wherein the thermal dissipation device further comprises:

a plurality of heat dissipating fins, each being disposed in a direction parallel with the flowing direction.

5. The heat exchange chamber of claim 1, wherein the portion of the cavity that is not occupied by the thermal dissipation device forms an accommodation space to be provided for the vaporized cooling fluid to accumulate thereat, and the accommodation space is constructed in a manner selected from the group consisting of: the accommodation space is in communication with a portion of the outlet, and the accommodation space is in communication with all the outlet.

6. The heat exchange chamber of claim 1, wherein the diameter of the outlet is larger than that of the inlet.

7. A heat exchange chamber for liquid state cooling fluid, comprising:

a casing, configured with a cavity having an accommodation space formed therein, an inlet and an outlet in a manner that the inlet is provided for allowing a cooling fluid to flow into the cavity and the outlet is provided for allowing the cooling fluid to flow out of the cavity; and

a thermal dissipation device, disposed inside the cavity for occupying the remaining space thereof other than the accommodation space, and provided for allowing a portion of the cooling fluid to flow therethrough so as to be vaporized;

wherein, the cooling fluid is enabled to flow through the cavity in a flowing direction; and the cross-sectional area of the accommodation space that is perpendicular to the flowing direction is constructed increasing gradually along the flowing direction in a manner selected from the group consisting of: a linear manner and a non-linear manner, so as to cause pressure differences along the flowing direction inside the accommodation space.

8. The heat exchange chamber of claim 7, wherein the thermal dissipation device further comprises: a plurality of heat dissipating fins, each being disposed in a direction parallel with the flowing direction.

9. The heat exchange chamber of claim 7, wherein the casing further comprises: a base, being provided for engaging with a heat source while being arranged in thermal contact with the thermal dissipation device.

10. The heat exchange chamber of claim 8, wherein the height of each heat dissipating fin is constructed tapering along the flowing direction.

11. The heat exchange chamber of claim 7, wherein the accommodation space is provided for the vaporized cooling fluid to accumulate thereat, and the accommodation space is constructed in a manner selected from the group consisting of: the accommodation space is in communication with a portion of the outlet, and the accommodation space is in communication with all the outlet.

12. The heat exchange chamber of claim 7, wherein the diameter of the outlet is larger than that of the inlet.