WO2012152018A1

WO2012152018A1 - Planar heat-pipe heat exchanger

Info

Publication number: WO2012152018A1
Application number: PCT/CN2011/084561
Authority: WO
Inventors: 朱旺法; 薛松; 鞠金培; 刘欣; 易杰; 景佰亨; 郭雨龙
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-07-01
Filing date: 2011-12-23
Publication date: 2012-11-15
Also published as: CN102261862A; CN102261862B

Abstract

A planar heat-pipe heat exchanger comprising: a housing (1), a sealed steam cavity (2) within the housing (1), and a working fluid (52) provided within the steam cavity (2). The planar heat-pipe heat exchanger is provided with a condensation face (7) and an evaporation face (6). The steam cavity (2) is surrounded by the condensation face (7), the evaporation face (6), and four lateral faces. The condensation face (7) has arranged on the top thereof a condensation face groove aggregator (3). The evaporation face (6) has arranged at the bottom thereof an evaporation face groove aggregator (5). The condensation face groove aggregator (3) and the evaporation face groove aggregator (5) are connected via internal grooves (4) arranged on the interior wall of the steam cavity (2). The planar heat-pipe heat exchanger allows for effectively reduced temperature of power tube components, thereby ensuring reliable, safe, and stable system operation.

Description

Flat heat pipe heat exchanger

The invention relates to the technical field of heat exchangers, in particular to a flat heat pipe heat exchanger. Background technique

The heat pipe can quickly pass the heat generated by the high-heat heat source through the vaporizing subtropical zone. Because of the large latent heat of vaporization, the temperature of the heated surface can be instantaneously reduced, thereby effectively reducing the temperature of the heat source and improving the reliability of the system.

In the RRU (Radio Remote Unit) product, the power consumption of the power tube is up to several hundred watts. The traditional solution is to: solder the power tube on the copper substrate, and use the good thermal conductivity of copper to quickly heat the local heat source. Expanding around, increasing the effective heat dissipation area, and efficiently transferring heat to the heat dissipating fins, thereby reducing the temperature of the heat source.

However, the above methods have been unable to meet the increasing demand for power tube heat consumption. Since the power tube has a large heat consumption, the heat consumption of the power tube cannot be effectively taken out of the system, which not only affects the life of the power tube itself, but also affects the reliability of the entire system. Therefore, VC (Vapour Cavity) heat pipes have appeared, and their shape and shape are similar. Since the capillary core structure (sintered copper powder and wire mesh) is used inside, the horizontal direction (tangential) has a large thermal conductivity, so the thermal resistance is small, and the heat of the heat source can rapidly spread to the entire surface. Therefore, In the traditional copper block heat dissipation, the heat dissipation effect is more remarkable.

The application of VC steam chamber heat pipe on RRU shows that no matter what structure is adopted, as long as the heat can be quickly diffused (showing good uniform temperature performance on the contact surface with the heat source), the temperature of the heat source can be effectively reduced, and the whole system can be improved. reliability. However, the VC steam cavity heat pipe has a fatal disadvantage in that the external dimensions are limited. When the external dimensions are increased to a certain extent, the heat pipe cannot work, and the heat transfer effect of the entire heat pipe is even worse than that of the copper block. The main reason is that when the external dimensions increase, The capillary force (a force that drives the flow of the liquid caused by the surface tension) cannot overcome the flow resistance of the liquid. At this time, the VC steam chamber heat pipe cannot work, and thus the heat transfer performance is drastically deteriorated. Summary of the invention

The technical problem to be solved by the present invention is to provide a flat heat pipe heat exchanger for solving the problem that the heat dissipation performance of the prior art steam cavity heat pipe is limited by the structure size.

In order to solve the above technical problem, the present invention provides a flat heat pipe heat exchanger, the heat exchanger comprising: a casing, the inside of the casing is a closed steam chamber; the steam chamber is provided with a working liquid; The heat exchanger is provided with a condensation surface and an evaporation surface, a top surface of the condensation surface is provided with a condensation surface groove collector; a bottom surface of the evaporation surface is provided with a evaporation surface groove collector; the condensation surface groove collector and the evaporation surface The groove collector is in communication through an internal groove disposed on an inner wall of the steam chamber.

Further, the internal grooves are one or more.

Further, the inner groove includes a condensation surface inner groove and an evaporation surface inner groove, and the condensation surface inner groove extends downward with the condensation surface groove collector as a vertex; the evaporation surface inner groove is The evaporation surface groove collector extends upward from the apex and communicates with the internal groove of the condensation surface to form a closed loop.

Further, the working liquid is water, ammonia or a refrigerant.

Further, the evaporation surface groove collector is filled with a porous metal foam, a wire mesh, and/or a sintered metal powder.

Further, a portion of the outer casing corresponding to the condensing surface is provided with heat dissipating fins, or a groove is formed.

Further, the inner groove is semicircular, square, trapezoidal or triangular.

The beneficial effects of the present invention are as follows:

The invention absorbs the heat of the heat source through the working liquid in the evaporation surface groove collector, and the generated steam liquefies and radiates heat on the condensation surface through the steam chamber, and the heat is radiated to the surrounding environment, and the steam is on the condensation surface. After condensing in the groove collector, under the action of gravity and capillary force, it flows along the internal groove to the evaporation surface groove collector to realize circulation. The invention can effectively reduce the temperature of the power tube device, thereby ensuring reliable, safe and stable operation of the system. DRAWINGS

1 is a schematic structural view of a flat heat pipe heat exchanger according to an embodiment of the present invention;

Figure 2 is a cross-sectional view taken along line A-A of Figure 1;

Figure 3 is a cross-sectional view taken along line B-B of Figure 1;

Figure 4 is a perspective view showing the internal structure of the internal groove of Figure 1;

Figure 5 is a cross-sectional view taken along line C-C of Figure 1. detailed description

In order to solve the problem that the heat dissipation performance of the prior art steam chamber heat pipe is limited by the structure size, the present invention provides a flat heat pipe heat exchanger. The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

1 is a schematic structural view of a flat heat pipe heat exchanger according to an embodiment of the present invention, wherein the broken line in FIG. 1 indicates the internal structure of the flat heat pipe heat exchanger. As shown in FIG. 1 to FIG. 5, an embodiment of the present invention relates to a flat heat pipe heat exchanger, comprising: a casing 1 having a closed steam chamber 2 inside the casing 1; a working liquid 52 disposed in the steam chamber 2; The evaporation surface 6 and the condensation surface 7 and the four side surfaces are surrounded, wherein the evaporation surface 6 refers to a surface that absorbs heat of the heat source through the working liquid 52 in the evaporation surface groove collector 5; the condensation surface 7 is a surface that is directed to the external heat dissipation. When the outer casing 1 adopts a six-sided square structure, the two largest surfaces are the evaporation surface 6 and the condensation surface 7, respectively, and the remaining four surfaces are the upper and lower bottom surfaces and the left and right side surfaces, respectively. The top of the condensation surface 7 is provided with a condensation surface groove collector 3; the bottom of the evaporation surface 6 is provided with a evaporation surface groove collector 5; the condensation surface groove collector 3 and the evaporation surface groove collector 5 are disposed on the inner wall of the steam chamber 2 The upper inner groove 4 is connected. The inner grooves 4 may be one piece or a plurality of pieces, and in the case of a plurality of pieces, each of them communicates with the condensing surface groove concentrator 3 and the evaporation surface groove concentrator 5. The inner groove 4 includes a condensation face inner groove 41 and an evaporation face inner groove 42. The condensation face inner groove 41 extends downward with the condensation face groove collector 3 as a vertex, and the groove of the condensation section has a 'Ά'shape; The evaporation surface inner groove 42 extends upward from the evaporation surface groove collector 5 and communicates with the condensation surface inner groove collector 3 to form a closed loop. The evaporation section groove and the condensation section groove have opposite shapes. 'Ύ' shape. The groove is also provided with grooves on both sides of the vapor chamber 2 connecting the condensation surface 7 and the evaporation surface 6, for connecting the condensation surface inner groove 41 and the evaporation surface inner groove 42 to form a closed loop. The shape of the inner groove 4 may be semicircular, square, trapezoidal or triangular. Among them, the semicircle includes an "Ω" shape, an ellipse shape, a quarter circle shape, a three-quarter circle shape, a circular arc shape, and the like. The trapezoid includes a trapezoid with a small upper bottom, a large trapezoid with a large lower bottom, and a small dovetail with a large upper and lower bottom.

The entire flat heat pipe radiator of this embodiment is placed in a vertical position; the portion of the outer casing 1 corresponding to the condensation surface 7 is provided with heat dissipating fins, or a groove is formed. For the RRU type natural heat dissipation product (the cold source is air), the outer casing 1 corresponding to the condensation surface 7 is provided with fins to increase the effective condensation area. When the cold source is a liquid, a "U" shaped channel or a fractal tree structure can be directly placed on the condensing surface of the casing to enhance heat exchange.

The housing material of the outer casing 1 may be a variety of high thermal conductivity metals such as copper and aluminum alloy.

The working fluid 52 is water, ammonia or a plurality of refrigerants. The evaporation face groove collection 5 is filled with a porous metal foam, a wire mesh and/or a sintered metal powder, or various composite heat source wick structures 51. The wick can enhance the capillary driving force, not only can quickly evaporate or boil the working liquid, form steam 8, and can quickly flow the liquid in the condensing section to the evaporation point, thereby improving the heat exchange efficiency.

The working principle of the flat heat pipe heat exchanger of the present invention is that the flat heat pipe heat exchanger is placed vertically, the evaporation surface groove collector 5 is located at the bottom of the evaporation surface 6, and the condensation section groove collector 3 is located at the condensation surface 7. The top. The position of the heat source 10 is close to the bottom of the flat heat pipe heat exchanger of the embodiment of the present invention. The flat heat pipe of the embodiment uses the working liquid (working liquid 52) in the groove collector 5 of the evaporation section. The heat of the power tube is absorbed to generate an evaporation phase change, and the steam 8 generated by the vapor phase transition from the heat source point rapidly flows through the steam chamber 2 to the condensation surface 7 of a larger area, and the heat is released after the condensation surface 7 is condensed, passing through the condensation surface 7 Direct transmission to external sources of cold. The condensate produced by the vapor 8 after liquefaction on the condensing surface 7 flows downward in both directions of the inner groove 41 of the condensing surface under the double driving of capillary force and gravity, and passes through the side wall groove to the inner groove 42 of the evaporation surface. Go to the evaporation section groove collector 5. The working liquid in the evaporation section groove collector 5 again absorbs the heat of the high heat flow heat source 10 to generate steam 8, which is condensed by the steam chamber 2 to the condensation surface 7. In this way, the heat transfer in the heat pipe is realized by the capillary pump pressure and the gravity, and the heat of the heat source 10 can be quickly absorbed, thereby effectively reducing the temperature of the heat source 10.

Since the flat heat pipe heat exchanger of the embodiment of the invention can quickly pass the heat generated by the high heat flow heat source point through the vaporization latent tropical zone, the latent heat of the vaporization is large, so that the temperature level of the heating surface can be instantaneously reduced, so that the flat heat pipe heating surface has superior isothermal temperature. Performance, effectively reducing the temperature of the power tube device, thus ensuring reliable, safe and stable operation of the system. It can not only overcome the shortcomings of the copper block unable to transmit large heat in a limited space, but also overcome the shortcomings of the VC steam cavity heat pipe structure when it has a large size. Its special 'Ά' shape and 'Ύ' shape of the internal groove structure can not only effectively utilize the suction driving effect of the capillary force, but also make full use of the action of gravity to quickly return the condensate from the condensation section to the evaporation section; The composite wick structure of the inner groove of the evaporation surface and the wire mesh can provide a strong capillary driving force, and also allows the liquid in the condensing section to quickly flow back to the evaporation section. This greatly increases the maximum heat transfer capacity. Therefore, it can effectively eliminate local hot spots, improve the temperature uniformity of the heating surface and reduce the temperature of the power tube, thereby reducing the overall system temperature and ensuring reliable, safe and stable operation of the system. In addition, the flat heat pipe heat exchanger of the embodiment of the invention has the characteristics of simple structure, convenient processing and strong operability.

While the preferred embodiments of the present invention have been disclosed for purposes of illustration, those skilled in the art will recognize that various modifications, additions and substitutions are possible, and the scope of the invention should not be limited to the embodiments described above.

Claims

Claim

A flat heat pipe heat exchanger, characterized in that: the heat exchanger comprises: a casing, the inside of the casing is a closed steam chamber; a working liquid is arranged in the steam chamber; and the flat heat pipe heat exchanger a condensation surface and an evaporation surface are disposed, the condensation surface is provided with a condensation surface groove collector; the evaporation surface bottom is provided with an evaporation surface groove collector; the condensation surface groove collector and the evaporation surface groove are collected The device communicates through an internal groove disposed on an inner wall of the vapor chamber.

2. The flat heat pipe heat exchanger according to claim 1, wherein said internal grooves are one or more.

The flat heat pipe heat exchanger according to claim 1 or 2, wherein the inner groove comprises a condensation face inner groove and an evaporation face inner groove, and the condensation face inner groove is condensed The surface groove collector extends downwardly from the apex; the evaporation surface inner groove extends upward from the evaporation surface groove collector and communicates with the internal groove of the condensation surface to form a closed loop.

The flat heat pipe heat exchanger according to claim 1 or 2, wherein the working liquid is water, ammonia water or a refrigerant.

The flat heat pipe heat exchanger according to claim 1 or 2, wherein the evaporation surface groove collector is filled with a porous metal foam, a wire mesh, and/or a sintered metal powder.

The flat heat pipe heat exchanger according to claim 1 or 2, wherein the portion of the outer casing corresponding to the condensing surface is provided with heat dissipating fins or is machined with a groove.

The flat heat pipe heat exchanger according to claim 1 or 2, wherein the inner groove is semicircular, square, trapezoidal or triangular.