Pulsating heat pipe system capable of expanding heat exchange area

Abstract

The invention provides a pulsating heat pipe system for expanding the heat exchange area, the system comprises a pulsating heat pipe, the pulsating heat pipe comprises a lower bending structure and an upper bending structure, the lower bending structure comprises a vertical pipe extending in the up-down direction and a connecting pipe communicating the upper end and the lower end of the adjacent vertical pipe, and the upper bending structure comprises an upper bending structure and a lower bending structure; the upper bent structure comprises horizontal pipes extending in the horizontal direction and connecting pipes communicating the left ends and the right ends of the adjacent horizontal pipes, the upper bent structure and the lower bent structure form a series loop structure through the connecting pipes, the pulsating heat pipe comprises an evaporation end and a condensation end, the evaporation end comprises the lower portion of the lower bent structure, and the condensation end comprises the lower portion of the lower bent structure. The condensation end comprises an upper portion of a lower bent structure and an upper bent structure. According to the pulsating heat pipe system capable of expanding the heat exchange area, through the arrangement of the upper bent structure, the heat exchange area of the condensation end can be increased, and the heat exchange effect is improved.

Description

Technical Field

[0001] The present invention relates to a heat exchanger, in particular to a pulsating heat pipe heat exchanger. Background Art

[0002] Heat pipe technology, a highly efficient phase-change heat transfer element, originated in 1963 and was invented by George Grover of the Los Alamos National Laboratory in the United States. It fully utilizes the principles of heat conduction and the rapid heat transfer properties of phase-change media to quickly transfer heat from a heating object to the outside of the heat source through a heat pipe. Its thermal conductivity exceeds that of any known metal.

[0003] Pulsating heat pipes, also known as oscillating heat pipes, were proposed by Japanese scholar H. Akachi in the 1990s. Existing pulsating heat pipes are simple but complex two-phase heat transfer devices. They involve evacuating a long capillary tube and then filling it with liquid. If the capillary diameter is small enough, vapor and liquid plugs will intermittently form within the tube. When heated at one end of the pulsating heat pipe, the liquid evaporates, and the vapor flows to the other end under a slight pressure differential, releasing heat and condensing into liquid. The small tube diameter and repeated bending at the hot and cold ends are the two essential requirements for a pulsating heat pipe, which transfers heat through phase change and pulsating vapor and liquid. Compared to conventional heat pipes, they offer a simpler structure, require no wick, are unaffected by gravity, and have a smaller diameter, allowing for arbitrary bends and greater adaptability, resulting in lower manufacturing, operating, and maintenance costs. Due to their excellent performance, pulsating heat pipes are considered the most promising heat transfer element for dissipating high heat flux in small spaces.

[0004] A common problem with existing pulsating heat pipes, such as those disclosed in CN104848718A and CN106643241A, is that the heat exchange area at the condensing end is too small, resulting in poor heat dissipation. Therefore, improvements are needed to optimize the heat exchange effect. Summary of the Invention

[0005] In order to overcome the defects and shortcomings in the prior art, the present invention provides a pulsating heat pipe system with an expanded heat exchange area, which can expand the heat exchange area at the condensation end and improve the heat exchange effect.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows:

[0007] A pulsating heat pipe system for expanding the heat exchange area, the system comprising a pulsating heat pipe, the pulsating heat pipe comprising a lower bending structure and an upper bending structure, the lower bending structure comprising a vertical pipe extending in the up-down direction and a connecting pipe connecting the upper and lower ends of adjacent vertical pipes, the upper bending structure comprising a horizontal pipe extending in the horizontal direction and a connecting pipe connecting the left and right ends of adjacent horizontal pipes, the upper bending structure and the lower bending structure forming a series loop structure through the connecting pipe, the pulsating heat pipe comprising an evaporating end and a condensing end, the evaporating end comprising the lower portion of the lower bending structure, and the condensing end comprising the upper portion of the lower bending structure and the upper bending structure.

[0008] As an improvement, the lower part of the lower bending structure includes the lower part of the vertical tube and a connecting tube communicating with the lower ends of adjacent vertical tubes.

[0009] As an improvement, the upper part of the lower bending structure includes the upper part of the vertical tube and a connecting tube connected to the upper end of the vertical tube.

[0010] As an improvement, the condensation end is arranged in the heat exchange box to transfer heat to the fluid in the heat exchange box.

[0011] As an improvement, the heat exchange box is divided into an upper box and a lower box that are independent of each other by a partition. The upper box and the lower box have a fluid outlet and a fluid inlet respectively, wherein the upper bending structure is arranged in the upper box, and the upper part of the lower bending structure is arranged in the lower box.

[0012] As an improvement, a horizontal baffle is arranged in the upper box body, and the horizontal baffle includes a left baffle and a right baffle extending from the left and right walls of the box body to the center, and the left baffle and the right baffle are arranged at intervals, and the horizontal baffle is arranged between adjacent horizontal tubes, and the inlet and outlet of the upper box body are arranged so that the flow direction of the fluid in the box body is opposite to that of the fluid in the horizontal straight tube; a vertical baffle is arranged in the lower box body, and the vertical baffle includes a lower baffle extending upward from the lower wall of the box body and an upper baffle extending downward from the partition, and the lower baffle and the upper baffle are arranged at intervals, and the vertical baffle is arranged between adjacent vertical tubes, and the inlet and outlet of the lower box body are arranged so that the flow direction of the fluid in the lower box body is opposite to that of the fluid in the vertical tube; the partition is a heat conductor, and the inlet and outlet of the upper box body and the inlet and outlet of the lower box body are arranged so that the flow direction of the fluid in the upper box body is opposite to that of the fluid in the lower box body.

[0013] As an improvement, the inlet and the outlet of the upper box are respectively arranged on the right side and the left side of the upper box.

[0014] As an improvement, the inlet and the outlet of the lower box are respectively arranged on the left and right sides of the lower box.

[0015] As an improvement, the volume of the upper box is 1.5-5 times the volume of the lower box.

[0016] As an improvement, along the flow direction of the fluid in the upper box, the distance between adjacent horizontal tubes of the upper box becomes smaller and smaller.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. The present invention provides an upper curved structure at the condensing end. The upper curved structure includes horizontal tubes extending horizontally and connecting tubes connecting the left and right ends of adjacent horizontal tubes. This expands the heat exchange area at the condensing end and improves the heat exchange effect. Moreover, because the upper curved structure is a horizontal tube extending horizontally, it is perpendicular to the flow direction of the lower curved vertical tube, forming a cross flow direction, further improving the heat exchange effect.

[0019] 2. The present invention divides the condensing end box into two parts, and the two parts exchange heat with different fluids respectively, which can facilitate the configuration of different fluid directions. For example, the heat exchange fluid in each box is close to countercurrent heat exchange, thereby improving the heat exchange effect. At the same time, the fluids in the upper and lower boxes can also exchange heat in countercurrent. The countercurrent flow in three major directions further improves the heat exchange effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the pulsating heat pipe structure of the present invention;

[0021] Figure 2 It is a structural schematic diagram of a pulsating heat pipe system provided with a heat exchange box according to the present invention.

[0022] Figure 3 It is a schematic structural diagram of the preferred fluid flow direction of the pulsating heat pipe system of the present invention. DETAILED DESCRIPTION

[0023] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0024] In this article, unless otherwise specified, “ / ” represents division, and “×” and “*” represent multiplication.

[0025] It should be noted that, unless otherwise specified, the directional terms "up", "down", "left", "right", "vertical", and "horizontal" in the present invention do not represent actual directions, but are only for the convenience of expression. Figure 1 The pulsating heat pipe in the "up", "down", "left" and "right" four positions. "Vertical" and "horizontal" respectively represent Figure 1 The "vertical" and "horizontal" directions of the pulsating heat pipe in the main view angle are for convenience of description and do not represent the true "vertical" and "horizontal" directions.

[0026] Figure 1-3A pulsating heat pipe system that expands the heat exchange area is demonstrated. Figure 1 As shown, the system includes a pulsating heat pipe, which includes a lower bending structure 1 and an upper bending structure 2. The lower bending structure 1 includes a vertical tube 11 extending in the up and down directions and a connecting tube 12 connecting the upper and lower ends of adjacent vertical tubes. The upper bending structure includes a horizontal tube 21 extending in the horizontal direction and a connecting tube 22 connecting the left and right ends of adjacent horizontal tubes. The upper bending structure and the lower bending structure form a series loop structure through the connecting tube 3. The pulsating heat pipe includes an evaporating end and a condensing end. The evaporating end includes the lower part of the lower bending structure, and the condensing end includes the upper part of the lower bending structure and the upper bending structure.

[0027] The present invention provides an upper curved structure at the condensing end. The upper curved structure includes horizontal tubes extending horizontally and connecting tubes connecting the left and right ends of adjacent horizontal tubes. This expands the heat exchange area at the condensing end and improves the heat exchange effect. Furthermore, because the upper curved structure is a horizontal tube extending horizontally, it flows perpendicularly to the lower curved vertical tube. This allows the fluid to form a cross structure with at least a portion of the condensing end during heat exchange, avoiding simple downstream flow and further improving the heat exchange effect.

[0028] As an improvement, the lower portion of the lower bending structure 1 includes the lower portion of the vertical tube 11 and a connecting tube 12 communicating with the lower ends of adjacent vertical tubes.

[0029] As an improvement, the upper portion of the lower bending structure 1 includes the upper portion of the vertical tube 11 and a connecting tube 12 communicating with the upper end of the vertical tube.

[0030] Through the above arrangement, the condensation end also includes the upper connecting tube of the lower bent structure and the upper straight tube, which expands the heat exchange area. Moreover, because the upper bend is a horizontal tube extending in the horizontal direction, it is in a vertical flow direction with the lower bent vertical tube. The fluid can form a cross structure with at least a part of the condensation end during heat exchange, avoiding simple downstream flow and further improving the heat exchange effect.

[0031] As an improvement, the condensation end is arranged in the heat exchange box 3 to transfer heat to the fluid in the heat exchange box.

[0032] As an improvement, the heat exchange housing 3 is divided into an independent upper housing 31 and lower housing 32 by a partition 4. The upper and lower housings each have a fluid outlet and a fluid inlet. The upper portion of the bent structure is located within the upper housing, while the upper portion of the lower bent structure is located within the lower housing. By providing two independent housings, the upper and lower housings can heat different fluids, thereby outputting fluids at a variety of different temperatures, meeting the diverse output fluid needs of different users.

[0033] As an improvement, a horizontal baffle 311 is provided in the upper box body. Figure 2The horizontal baffle includes a left baffle and a right baffle extending from the left and right walls of the box to the center, the left baffle and the right baffle are spaced apart, the horizontal baffle is arranged between adjacent horizontal tubes, and the inlet and outlet of the upper box are arranged so that the flow direction of the fluid in the box is opposite to that of the fluid in the horizontal straight tube; a vertical baffle 321 is arranged in the lower box, the vertical baffle includes a lower baffle extending upward from the lower wall of the box and an upper baffle extending downward from the partition, the lower baffle and the upper baffle are spaced apart, the vertical baffle is arranged between adjacent vertical tubes, and the inlet and outlet of the lower box are arranged so that the flow direction of the fluid in the lower box is opposite to that of the fluid in the vertical tube; the partition is a heat conductor, and the inlet and outlet of the upper box and the inlet and outlet of the lower box are arranged so that the flow direction of the fluid in the upper box is opposite to that of the fluid in the lower box.

[0034] The present invention divides the condensing end box into two parts, and the two parts exchange heat with different fluids respectively, which can facilitate the configuration of different fluid directions. For example, the heat exchange fluid in each box is close to countercurrent heat exchange, thereby improving the heat exchange effect. At the same time, the fluids in the upper and lower boxes can also exchange heat in countercurrent flow. The countercurrent flow in three major directions further improves the heat exchange effect.

[0035] It should be noted that the counter-flow of the fluids in the upper and lower boxes is a counter-flow in a general direction, for example Figure 3 As shown in Figure 2, the two fluids flow from left to right and from right to left respectively.

[0036] As an improvement, Figure 3 As shown, when the number of horizontal baffles is even, the inlet and outlet of the upper box are respectively arranged on both sides of the upper box, for example Figure 1 The right and left sides. Preferably, the upper part of the left side and the lower part of the right side. When the number of horizontal baffles is odd, the inlet and outlet of the upper box body are respectively arranged on the same side of the upper box body, for example, at the same time on the left and right sides.

[0037] As an improvement, Figure 3 As shown, the inlet and outlet of the lower box are respectively arranged on the left and right sides of the lower box.

[0038] As an improvement, the flow direction of the fluid in the heat pipe is from bottom to top in the leftmost connecting pipe 3 .

[0039] The above arrangement can form three countercurrent flows, thereby achieving the best heat exchange effect.

[0040] As an improvement, the volume of the upper box is 1.5-5 times the volume of the lower box.

[0041] As an improvement, the spacing between adjacent horizontal tubes in the upper box decreases along the flow direction of the fluid within the upper box until it reaches a certain point, then increases again. This is because numerical simulations and experiments have shown that under countercurrent heat transfer conditions with horizontal baffles, the heat transfer effect is best near the inlet and outlet, with the greatest temperature difference. Heat transfer decreases toward the middle, necessitating compensation for heat transfer in the middle to maximize overall heat transfer. Therefore, the horizontal tube spacing is varied to enhance heat transfer in the middle.

[0042] As an improvement, along the flow direction of the fluid in the upper box, the spacing between adjacent horizontal tubes of the upper box gradually increases in amplitude, and then gradually increases in amplitude. The above amplitude changes can further improve the heat exchange effect.

[0043] As an improvement, the certain position is set in the middle position of the upper box in the up-down direction.

[0044] As an improvement, the baffle is a heat conductor, allowing the fluids in the upper and lower channels to exchange heat through the baffle. By providing a heat-conducting baffle, heat exchange between the fluids in the upper and lower channels can be achieved, resulting in heat complementarity between the upper and lower channels. This allows the hotter fluid in the upper and lower channels to transfer heat to the cooler fluid, which then cools down and absorbs heat from the heat pipe, achieving maximum heat exchange. The heat conduction complementarity provided by the baffle ensures optimal heat exchange, whether forward or reverse flow.

[0045] As an improvement, the thermal conductivity of the partition varies at different locations, gradually decreasing from the center to the left and right sides. When the fluids in the upper and lower boxes flow in countercurrent, the inlet and outlet of the box are set on the left and right sides respectively. At this time, the temperature difference between the two is the largest, and the heat exchange effect is the best. Because the thermal conductivity of the middle position is increased, the heat exchange effect is increased, and the overall heat exchange is balanced, achieving overall heat exchange balance, thereby achieving the best heat exchange effect.

[0046] As an improvement, the thermal conductivity gradually decreases from the middle of the partition to the left and right sides. The above setting can further increase the heat exchange effect, so that the overall heat exchange is balanced, achieving overall heat exchange balance, thereby further achieving the best heat exchange effect.

[0047] Although the present invention has been disclosed above with reference to preferred embodiments, the present invention is not limited thereto. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope defined by the claims.

Claims

1. A pulsating heat pipe system for expanding a heat exchange area, the system comprising a pulsating heat pipe, the pulsating heat pipe comprising a lower bending structure and an upper bending structure, the lower bending structure comprising vertical tubes extending in an up-down direction and connecting tubes connecting the upper and lower ends of adjacent vertical tubes, the upper bending structure comprising horizontal tubes extending in a horizontal direction and connecting tubes connecting the left and right ends of adjacent horizontal tubes, the upper bending structure and the lower bending structure forming a series loop structure through the connecting tube, the pulsating heat pipe comprising an evaporating end and a condensing end, the evaporating end comprising a lower portion of the lower bending structure, and the condensing end comprising an upper portion of the lower bending structure and the upper bending structure.

2. The pulsating heat pipe system according to claim 1, characterized in that: The lower part of the lower bending structure includes the lower part of the vertical tube and a connecting tube communicating with the lower ends of adjacent vertical tubes.

3. The pulsating heat pipe system according to claim 2, wherein: The upper part of the lower bending structure includes the upper part of the vertical pipe and a connecting pipe communicating with the upper end of the vertical pipe.

4. The pulsating heat pipe system according to claim 3, characterized in that: The condensing end is arranged in the heat exchange box to transfer heat to the fluid in the heat exchange box.

5. The pulsating heat pipe system according to claim 4, characterized in that: The heat exchange box is divided into an upper box and a lower box which are independent of each other by a partition. The upper box and the lower box have a fluid outlet and a fluid inlet respectively. The upper bending structure is arranged in the upper box, and the upper part of the lower bending structure is arranged in the lower box.

6. The pulsating heat pipe system according to claim 5, characterized in that: A horizontal baffle is arranged in the upper box body, and the horizontal baffle includes a left baffle and a right baffle extending from the left and right walls of the box body to the center, and the left baffle and the right baffle are arranged at intervals, and the horizontal baffle is arranged between adjacent horizontal tubes, and the inlet and outlet of the upper box body are arranged so that the flow direction of the fluid in the box body is opposite to that of the fluid in the horizontal straight tube; a vertical baffle is arranged in the lower box body, and the vertical baffle includes a lower baffle extending upward from the lower wall of the box body and an upper baffle extending downward from the partition, and the lower baffle and the upper baffle are arranged at intervals, and the vertical baffle is arranged between adjacent vertical tubes, and the inlet and outlet of the lower box body are arranged so that the flow direction of the fluid in the lower box body is opposite to that of the fluid in the vertical tube; the partition is a heat conductor, and the inlet and outlet of the upper box body and the inlet and outlet of the lower box body are arranged so that the flow direction of the fluid in the upper box body is opposite to that of the fluid in the lower box body.

7. The pulsating heat pipe system according to claim 6, wherein: The inlet and the outlet of the upper box body are respectively arranged on the right side and the left side of the upper box body.

8. The pulsating heat pipe system according to claim 6, wherein: The inlet and the outlet of the lower box are respectively arranged on the left side and the right side of the lower box.

9. The pulsating heat pipe system according to claim 6, wherein: The volume of the upper box is 1.5-5 times the volume of the lower box.

10. The pulsating heat pipe system according to claim 6, wherein: Along the flow direction of the fluid in the upper box, the distance between adjacent horizontal tubes of the upper box becomes smaller and smaller.

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