A micro jet cooling plate with porous heat transfer surface and a manufacturing method thereof

Abstract

The present invention discloses a micro jet cooling plate with a porous heat transfer surface, wherein a porous super hydrophilic surface structure composed of a plurality of evenly distributed small holes is centrally arranged on a rectangular working surface of the micro jet cooling plate, two cooling liquid outlet channels are arranged in parallel at two opposite sides of the working surface, and cooling liquid collecting channels with two ends connected to the cooling liquid outlet channels are arranged in parallel at the other two opposite sides of the working surface, and a plurality of micro channels are evenly connected between the porous super hydrophilic surface structure and the cooling liquid outlet channels and the cooling liquid collecting channels. The present invention also discloses a method for manufacturing a micro jet cooling plate with a porous heat transfer surface. The present invention can reduce the thermal resistance of the channel surface, increase the phase change heat transfer efficiency, and can effectively solve the problems of excessively high local temperature and uneven distribution of concentrated photovoltaic cells, thereby improving the power generation efficiency of the cells.

Description

Technical Field

[0001] The invention relates to the technical field of cooling of concentrated photovoltaic cell panels, and in particular to a micro jet cooling plate with a porous heat transfer surface and a manufacturing method thereof. Technical Background

[0002] As the third generation technology of solar power generation, concentrated solar energy technology absorbs more heat as the radiation intensity of the panel per unit area increases, and the temperature control and heat dissipation of the battery become more prominent. Traditional heat exchange cooling devices are mostly made of heat exchange materials in contact with heat source components, and use circulating media to take away heat, which makes it difficult to achieve instant cooling and uniform temperature distribution of the battery. In this context, in order to solve the problems of excessively high local temperature and uneven distribution of concentrated photovoltaic cells, a new heat dissipation mechanism needs to be proposed, aiming to quickly reduce the temperature of photovoltaic cells and make their heat flux density more evenly distributed, thereby improving the efficiency of photovoltaic cells and increasing the life of the batteries. Summary of the invention

[0003] In view of the above technical problems, the present invention aims to provide a micro jet cooling plate with a porous heat transfer surface, which has a simple structure and can achieve efficient and uniform heat dissipation, and a manufacturing method thereof.

[0004] The present invention is achieved through the following technical solutions:

[0005] A micro jet cooling plate with a porous heat transfer surface is provided. A porous super hydrophilic surface structure composed of a plurality of evenly distributed small holes is centrally arranged on a rectangular working surface of the micro jet cooling plate. Two cooling liquid outlet channels are arranged in parallel at two opposite sides of the working surface. Cooling liquid collecting channels whose two ends are connected to the cooling liquid outlet channels are arranged in parallel at the other two opposite sides of the working surface. A plurality of micro channels are evenly connected between the porous super hydrophilic surface structure and the cooling liquid outlet channels and the cooling liquid collecting channels.

[0006] Furthermore, the pores of the porous super-hydrophilic surface structure are evenly distributed in a matrix.

[0007] Furthermore, the spacing distance between the small holes is 0.1 mm to 0.5 mm.

[0008] Furthermore, the radius of the small hole is 0.04 mm to 0.06 mm, and the hole depth is 0.08-0.11 mm.

[0009] Furthermore, the cross-sectional shape of the microchannel is rectangular.

[0010] Furthermore, the cross-sectional size of the microchannel is 0.5 mm×0.5 mm.

[0011] Furthermore, the bottom surface of the microchannel is a hydrophobic surface.

[0012] Furthermore, the contact angle of the hydrophobic surface is 120 degrees to 180 degrees.

[0013] A method for manufacturing the micro jet cooling plate as described above comprises the steps of:

[0014] 1) Processing the coolant outlet channel, coolant collection channel and microchannel on the surface of the smooth metal substrate;

[0015] 2) A porous super-hydrophilic surface structure is prepared in the middle area of ​​the metal substrate by using a particle sintering method;

[0016] 3) The bottom surface of the microchannel is treated with a hydrophobic surface by using a chemical deposition method.

[0017] Furthermore, in step 1), the coolant outlet channel, the coolant collection channel and the microchannel are machined on the surface of the smooth metal substrate by a mechanical machining method of plowing and extrusion.

[0018] Compared with the prior art, the present invention is based on the principle of activated core boiling, and adds a porous super-hydrophilic surface structure with fixed vaporization core holes within the jet impact plane. The hole structure can increase the frequency of bubble detachment, and the super-hydrophilic surface promotes the timely replenishment of boiling bubbles detached from the liquid phase, thereby realizing instantaneous heat exchange for local high temperature. At the same time, the hydrophobic surface micro-channels evenly arranged around it can reduce the thermal resistance of the channel surface, increase the phase change heat transfer efficiency, and effectively solve the problems of excessive local temperature and uneven distribution in the middle of the concentrated photovoltaic cell, thereby improving the battery power generation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a working diagram of a micro jet cooling system with a porous heat transfer surface according to an embodiment of the present invention.

[0020] Figure 2 It is a front view schematic diagram of a micro jet cooling plate with a porous heat transfer surface according to an embodiment of the present invention.

[0021] Figure 3 It is a three-dimensional schematic diagram of a micro jet cooling plate with a porous heat transfer surface according to an embodiment of the present invention.

[0022] In the figure: 1-flow pump; 2-upper cavity; 3-micro-injector; 4-lower cavity; 5-micro-jet cooling plate; 6-concentrating photovoltaic panel; 7-pipeline; 8-cooling tank; 9-external heat sink; 10-fan; 11-coolant storage tank; 12-coolant outlet channel; 13-micro channel; 14-porous super-hydrophilic surface structure; 15-coolant separation channel. DETAILED DESCRIPTION

[0023] The purpose of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments cannot be described one by one here, but the implementation mode of the present invention is not therefore limited to the following embodiments.

[0024] Embodiment 1

[0025] like Figure 2 As shown, a micro jet cooling plate with a porous heat transfer surface is added, wherein a porous super hydrophilic surface structure 14 composed of a plurality of evenly distributed small holes is centrally arranged on a rectangular working surface of the micro jet cooling plate, two cooling liquid outlet channels are arranged in parallel at two opposite sides of the working surface, and a cooling liquid collecting channel 15 with two ends connected to the cooling liquid outlet channels is arranged in parallel at the other two opposite sides of the working surface, and a plurality of micro channels 13 are evenly connected between the porous super hydrophilic surface structure 14 and the cooling liquid outlet channels and the cooling liquid collecting channel 15. The cooling liquid is sprayed onto the porous structure cooling plate by a micro injector, flows through the evenly distributed micro channels 13, and then collects into the cooling liquid outlet channel 12 and the cooling liquid separation channel 15, and the cooling liquid is water, ethanol or a refrigerant.

[0026] The pores of the porous super-hydrophilic surface structure 14 are evenly distributed in a matrix, and the spacing of the pores is 0.1 mm to 0.5 mm. The radius of the pores is 0.04 mm to 0.06 mm, and the pore depth is 0.08-0.11 mm. The porous super-hydrophilic surface structure 14 can increase the frequency of bubble detachment, and its super-hydrophilic surface can promote the timely replenishment of boiling bubbles from the liquid phase, thereby realizing instantaneous heat exchange of local high temperature.

[0027] The cross-sectional shape of the microchannel 13 is rectangular, and the cross-sectional size is 0.5 mm×0.5 mm. Meanwhile, the bottom surface of the microchannel 13 is a hydrophobic surface with a contact angle of 120 to 180 degrees, thereby reducing the thermal resistance of the channel surface and increasing the phase change heat transfer efficiency.

[0028] like Figure 1As shown, the cooling system of the concentrated photovoltaic cell includes a liquid storage tank 11, a flow pump 1, a micro-flow injection device, and a cooling tank 8 which are sequentially connected through a pipeline 7 to form a circulation loop. A plurality of micro-injectors 3 are arranged between the upper cavity 2 and the lower cavity 4 of the micro-flow injection device. The micro-jet cooling plate 5 provided in the above embodiment is located at the bottom of the lower cavity 4. The porous super-hydrophilic surface structure 14 on the working surface of the micro-jet cooling plate 5 is arranged opposite to the micro-injector 3. The back of the micro-jet cooling plate 5 is arranged closely to the concentrated photovoltaic cell panel 6. The cooling tank 8 is provided with an external heat sink 9 and a fan 10. The size of the micro-jet cooling plate 5 is the same as that of the concentrated photovoltaic cell panel 6. The lower surface of the micro-jet cooling plate 5 is connected to the photovoltaic cell panel. In actual use, according to needs, a plurality of the micro-jet cooling plates 5 can be placed in parallel along the direction of the coolant outlet channel 12, and the parallel micro-jet cooling plates 5 are connected to each other, which can further improve the heat exchange effect.

[0029] The working process of the cooling system of the concentrated photovoltaic cell is as follows:

[0030] First, driven by the flow pump 1, the coolant enters the upper cavity 2 in the micro-flow injection device from the coolant storage tank 11. The coolant in the upper cavity 2 is sprayed onto the micro-jet cooling plate 5 through the micro-injector 3. The micro-jet cooling plate 5 is connected to the concentrating photovoltaic panel 6. The coolant takes away the heat of the concentrating photovoltaic panel 6. Then the coolant enters the cooling tank 8. Under the action of forced air cooling by the fan 10, the heat on the external heat sink 9 is taken away, so that the coolant is cooled again and enters the coolant storage tank 11 to complete a cycle.

[0031] Embodiment 2

[0032] A method for manufacturing the micro jet cooling plate as described above comprises the steps of:

[0033] 1) machining the coolant outlet channel, the coolant collection channel 15 and the microchannel 13 on the surface of the smooth metal substrate by a mechanical machining method of plowing and extrusion;

[0034] 2) Using particle sintering method to prepare porous super-hydrophilic surface structure in the middle area of ​​metal substrate14;

[0035] 3) The bottom surface of the microchannel 13 is treated with a hydrophobic surface by chemical deposition.

[0036] The above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A micro jet cooling plate with a porous heat transfer surface, Features: A porous super-hydrophilic surface structure (14) composed of a plurality of evenly distributed small holes is centrally arranged on the rectangular working surface of the micro jet cooling plate, the small holes of the porous super-hydrophilic surface structure (14) are evenly distributed in a matrix, two cooling liquid outlet channels (12) are arranged in parallel at two opposite sides of the working surface, a cooling liquid collecting channel (15) whose two ends are connected to the cooling liquid outlet channels (12) is arranged in parallel at the other two opposite sides of the working surface, a plurality of micro channels (13) are evenly connected between the porous super-hydrophilic surface structure (14) and the cooling liquid outlet channels and the cooling liquid collecting channels (15), and the bottom surface of the micro channels (13) is a hydrophobic surface.

2. The micro jet cooling plate according to claim 1, Features: The spacing distance between the small holes is 0.1 mm to 0.5 mm.

3. The micro jet cooling plate according to claim 1, Features: The radius of the small hole is 0.04 mm to 0.06 mm, and the hole depth is 0.08-0.11 mm.

4. The micro jet cooling plate according to claim 1, Features: The cross-sectional shape of the microchannel (13) is rectangular.

5. The micro jet cooling plate according to claim 4, Features: The cross-sectional size of the microchannel (13) is 0.5 mm×0.5 mm.

6. The micro jet cooling plate according to claim 1, Features: The contact angle of the hydrophobic surface is 120 to 180 degrees.

7. A method for manufacturing a micro jet cooling plate according to any one of claims 1 to 6, It is characterized in that Includes steps: 1) machining the coolant outlet channel, the coolant collection channel (15) and the microchannel (13) on the surface of a smooth metal substrate; 2) preparing a porous super-hydrophilic surface structure (14) in the middle area of ​​the metal substrate by a particle sintering method; 3) The bottom surface of the microchannel (13) is subjected to hydrophobic surface treatment by chemical deposition method.

8. The manufacturing method according to claim 7, Features: In the step 1), the coolant outlet channel (12), the coolant collection channel (15) and the microchannel (13) are machined on the surface of the smooth metal substrate by a mechanical machining method of plowing and extrusion.

Images