Submergence liquid cooling heat dissipation apparatus and electronic device

Abstract

Provided in the embodiments of the present application are a heat dissipation apparatus based on submergence phase-change liquid cooling technology, and an electronic device. The heat dissipation apparatus comprises a side wall and a plurality of liquid absorption columns, wherein the side wall encloses a cavity having two open ends; at least part of each liquid absorption column is located in the cavity, one end of each liquid absorption column is connected to one side of the inner surface of the side wall, and each liquid absorption column extends from one side of the inner surface to the opposite side; and each liquid absorption column comprises a porous structure. The electronic device comprises a housing, a cooling liquid, a heating device and the heat dissipation apparatus, wherein the cooling liquid, the heating device and the heat dissipation apparatus are all accommodated in the housing; the heating device and the heat dissipation apparatus are both submerged in the cooling liquid; and the heating device is fixed to the side of the side wall away from the liquid absorption columns. The embodiments of the present application can achieve efficient heat dissipation.

Description

Immersion liquid cooling heat dissipation device and electronic equipment Technical Field

[0001] The present application relates to the field of heat dissipation of electronic equipment, and in particular to an immersion liquid-cooled heat dissipation device and electronic equipment. Background Art

[0002] High-heat-flux electronic components operate in high-power, high-temperature environments, and their heat dissipation significantly impacts device reliability and overall system performance. Traditional cooling solutions, such as natural convection, forced air convection, and forced coolant convection, have limited heat dissipation capabilities and are unable to meet the cooling requirements of high-heat-flux electronic components.

[0003] Summary of the Invention

[0004] The embodiments of the present application provide an immersion liquid-cooled heat dissipation device and an electronic device, which can achieve efficient heat dissipation.

[0005] In a first aspect, an embodiment of the present application provides an immersion liquid-cooled heat dissipation device, comprising a side wall and a plurality of liquid wicking columns; the side wall forms a cavity with openings at both ends; at least a portion of each liquid wicking column is located in the cavity, one end of each liquid wicking column is connected to one side of the inner surface of the side wall, and each liquid wicking column extends in a direction from one side of the inner surface to the other side opposite to the one side; each liquid wicking column comprises a porous structure.

[0006] In this embodiment, by arranging multiple wicks, their porous structure can be utilized to more fully absorb the coolant, increasing the nucleation point and thereby achieving boiling at low superheat. This improves the boiling heat transfer coefficient, allowing for timely and rapid heat dissipation from the heat-generating device. By forming a cavity with open ends through the sidewalls, a drainage channel can be constructed. The "chimney effect" of this drainage channel ensures that the coolant continuously flows through the wick within it, regulating the flow of the coolant and preventing interference from other directions. This ensures orderly circulation of the coolant, enhances convective heat transfer, and achieves efficient heat dissipation.

[0007] In one implementation of the first aspect, each wick column includes a heat dissipation rib and a first wick. The first wick covers the periphery of the heat dissipation rib and comprises a porous structure. In this implementation, by covering the periphery of the heat dissipation rib with the first wick, the porous structure of the first wick can be utilized to enhance adsorption of coolant, increase nucleation points, and thus expand the heat dissipation area. The provision of the first wick enhances boiling treatment on the surface of the heat dissipation rib, which helps to increase the boiling heat transfer coefficient and thus enhance the heat dissipation effect. Compared with traditional solutions that rely solely on heat dissipation ribs to achieve boiling heat dissipation, this embodiment achieves superior heat dissipation effect.

[0008] In one implementation of the first aspect, a first groove is provided on the surface of the first wick of each wick column, and the first groove extends along the extension direction of the wick column. Providing the first groove can expand the adsorption area and heat dissipation area of ​​the first wick, thereby increasing the nucleation point, which is conducive to improving the boiling heat transfer coefficient and thus enhancing the heat dissipation effect.

[0009] In one implementation of the first aspect, the sidewall includes a base layer and a second wick, which are stacked together. The base layer is located on the side of the second wick away from the wick columns, and the second wick includes a porous structure. One end of each wick column is connected to the surface of the second wick away from the base layer. In this implementation, by providing the second wick on the sidewall, the porous structure of the second wick can be utilized to enhance adsorption of coolant, increase nucleation points, and thus expand the heat dissipation area. The provision of the second wick enhances boiling treatment of the sidewall, which helps to increase the boiling heat transfer coefficient and thus enhance the heat dissipation effect.

[0010] In one implementation of the first aspect, the surface of the second wick remote from the substrate includes a plurality of protrusions, a second groove is formed between each adjacent protrusion, and one end of the plurality of wick columns is connected to the surfaces of the plurality of protrusions. The provision of the second grooves can expand the adsorption and heat dissipation areas of the second wick, thereby increasing the nucleation point, thereby improving the boiling heat transfer coefficient and enhancing the heat dissipation effect.

[0011] In one implementation of the first aspect, the porous structure includes large pores and small pores, and the pore diameter of the large pores is larger than the pore diameter of the small pores. In the porous structure, the pores with larger pore diameters facilitate rapid escape of steam, while the pores with smaller pore diameters facilitate adsorption of coolant through capillary action. By designing a porous structure with multiple pore diameters, the pores with different pore diameters can cooperate with each other, and the rapid escape of steam and the on-demand distribution and replenishment of coolant can be achieved simultaneously. This can better balance the conflicting issues of steam escape and coolant absorption (steam escape requires a larger pore diameter, while capillary adsorption requires a smaller pore diameter), thereby enhancing the heat exchange efficiency of phase change heat transfer.

[0012] In one implementation of the first aspect, the porous structure is a microporous structure, wherein the micropores have a pore diameter of 100 nm to 200 nm. Setting the micropore diameter within this range facilitates more complete adsorption of the coolant, increases the nucleation point, and thereby achieves boiling at low superheat, improving the boiling heat transfer coefficient, and thus promptly and rapidly dissipating heat from the heat-generating device.

[0013] In one implementation of the first aspect, the sidewall includes multiple through-holes; the first portion of each heat dissipating rib is located within the cavity, and the second portion of each heat dissipating rib passes through a through-hole and is exposed outside the cavity. By designing the relative positions of the heat dissipating ribs and the sidewalls as described above, a balance can be achieved between the height of the liquid wicking column and the diameter of the drainage channel, ensuring that the overall heat dissipation performance of the heat dissipation device meets product requirements.

[0014] In one implementation of the first aspect, the first wick is positioned within the cavity and covers the outer periphery of the first portion of the heat dissipation rib. By designing the relative position of the first wick and the sidewall as described above, a balance can be achieved between the height of the first wick and the diameter of the drainage channel, ensuring that the overall heat dissipation performance of the heat dissipation device meets product requirements. Furthermore, a step can be formed between the first wick and the heat dissipation rib to facilitate assembly and positioning of the sidewall and the wick column.

[0015] In one implementation of the first aspect, the sidewalls include a first wall, a second wall, a substrate, and a third wall. The first wall, the second wall, the substrate, and the third wall are connected end-to-end to form a cavity, with the first wall facing the substrate and the second wall facing the third wall. One end of each wicking column is connected to a surface of the substrate facing the cavity. This sidewall structure is relatively simple, reliable to assemble, and well-suited for the interior space of electronic devices requiring heat dissipation.

[0016] In an implementation of the first aspect, the plurality of liquid-absorbing columns are integrated with the substrate. The integrated structure has good manufacturability and high assembly precision.

[0017] In one implementation of the first aspect, the first liquid wick is manufactured using a metal powder sintering process. Using the metal powder sintering process, a surface boiling enhancement treatment can be performed on the heat dissipation ribs through a mature and reliable process to ensure product performance.

[0018] In the second aspect, an embodiment of the present application provides an electronic device, including a shell, a coolant, a heating device and the heat dissipation device; the coolant, the heating device and the heat dissipation device are all accommodated in the shell, the heating device and the heat dissipation device are all immersed in the coolant, and the heating device is fixed on the side of the side wall away from the liquid absorption column.

[0019] The electronic device of this embodiment can utilize immersion liquid cooling and phase change heat dissipation. By arranging multiple wicks within the heat dissipation device, the porous structure of the wicks can be utilized to more fully adsorb the coolant, increasing the nucleation point and thereby achieving boiling at low superheat. This improves the boiling heat transfer coefficient, allowing for timely and rapid heat dissipation of the heat-generating device. By forming the side walls of the heat dissipation device into a cavity with open ends, a drainage channel can be constructed. The "chimney effect" of this drainage channel ensures that the coolant continuously flows through the wick within the drainage channel, regulating the flow of the coolant and avoiding interference from other directions. This ensures orderly circulation of the coolant, enhances convective heat transfer, and thus achieves efficient heat dissipation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG1 is a schematic diagram of the framework structure of an electronic device according to an embodiment of the present application;

[0021] FIG2 is a schematic structural diagram of a heat dissipation device and a heating element thereon in the electronic device of FIG1 ;

[0022] FIG3 is a schematic structural diagram of the heat dissipation device shown in FIG2 from another perspective;

[0023] FIG4 is a schematic diagram of the exploded structure of the heat dissipation device in FIG3 ;

[0024] FIG5 is a schematic structural diagram of a substrate and a liquid absorbing column of the heat dissipation device in FIG4 ;

[0025] FIG6 is a schematic diagram of the microstructure of the wick in the wick column;

[0026] FIG7 is a schematic diagram of a partially enlarged structure of point A in FIG5 ;

[0027] FIG8 is a schematic diagram of the working principle of the heat dissipation device according to an embodiment of the present application.

[0028] Figure numerals: 10-electronic device; 20-heat dissipation device; 30-housing; 40-heating device; 21-side wall; 21a-cavity; 21b-opening; 211-first wall; 211a-through hole; 212-second wall; 213-substrate; 214-base layer; 215-wick; 215a-boss; 215b-groove; 215c-top surface; 216-third wall; 22-wick column; 221-heat dissipation rib; 221a-upper end surface; 222-wick; 222a-upper end surface; 22c-step; 222b-groove. DETAILED DESCRIPTION

[0029] For ease of understanding, the relevant technical terms and expressions involved in the embodiments of this application are explained and described below.

[0030] The term "connect" should be interpreted broadly. For example, "connect" can mean either a detachable or non-detachable connection, a direct connection, or an indirect connection through an intermediary. The term "fix" should also be interpreted broadly. For example, "fix" can mean either a direct fixation or an indirect fixation through an intermediary.

[0031] The expression “A is formed on B” means that A is formed on the surface of B through a process, and all or part of A is bonded to the surface of B.

[0032] The directional terms mentioned in the embodiments of this application, such as "upper," "lower," "front," "back," "left," "right," "inner," "outer," "side," "top," and "bottom," are merely references to directions in the accompanying drawings. These directional terms are intended to better and more clearly illustrate and understand the embodiments of this application, and are not intended to explicitly or implicitly indicate that the devices or components referred to must have a specific orientation, be constructed or operate in a specific orientation, and are therefore not to be construed as limiting the embodiments of this application.

[0033] The term "and / or" simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or B exists alone.

[0034] The terms "first," "second," etc., are used solely for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly specifying the quantity of the technical features being referred to. Features designated "first," "second," etc., may explicitly or implicitly include one or more of such features.

[0035] The term "plurality" refers to two or more than two.

[0036] The embodiments of the present application are described below with reference to the accompanying drawings.

[0037] An embodiment of the present application relates to an electronic device 10 that uses immersion phase change liquid cooling technology for heat dissipation. The electronic device 10 includes but is not limited to IT (Information Technology) equipment such as servers (such as blade servers) or switches, or power converters (such as inverters, rectifiers), etc.

[0038] Figure 1 illustrates a frame-type structure of an electronic device 10. As shown in Figure 1 , electronic device 10 may include a housing 30, which may also be referred to as a chassis. Housing 30 may contain a coolant (indicated by a dashed curve). The coolant may be, for example, an insulating, low-boiling-point organic fluid or mixture thereof, including but not limited to electronic fluorinated fluids (such as FC-72, Novec 7000, or E1047), acetone, or the like.

[0039] As shown in FIG1 , various components can be installed within the housing 30, including several heating devices 40 that generate significant heat. The heating devices 40 include, but are not limited to, one or more of a chip (e.g., an optoelectronic chip), a power device (e.g., a diode, a transistor, a thyristor, a metal-oxide semiconductor field-effect transistor, an insulated gate bipolar transistor, etc.), a sensor, a circuit board, and the like. Illustratively, the heating device 40 can be a high-heat-current electronic component that can operate in a high-power, high-temperature environment. The heating device 40 can be fixed to the heat sink 20 and immersed in the coolant together with the heat sink 20. There can be one or more heat sinks 20, and each heat sink 20 can be fixed with several heating devices 40. The heat generated by the heating device 40 can be transferred to the heat sink 20, which can then exchange heat with the liquid coolant. The liquid coolant absorbs heat and vaporizes, and the vapor can rise and escape, thereby achieving heat dissipation of the heating device 40 through phase change and convection. In this embodiment, the coolant can be cooled by any suitable method so that the coolant can be recycled. For example, the steam may be condensed and liquefied by a condenser and its temperature may be reduced, and the low-temperature coolant may be used again to dissipate heat from the heat-generating device 40 .

[0040] The heat dissipation solution of this embodiment will be described in detail below.

[0041] 2 and 3 are schematic structural diagrams of the heat dissipation device 20 from different perspectives. As shown in FIG2 and FIG3 , the heat dissipation device 20 may include a side wall 21 and a plurality of liquid absorbing columns 22 .

[0042] As shown in Figures 2 and 3, the sidewall 21 may include multiple walls, which may be connected end to end to form a cavity 21a. These walls may be connected by any suitable means, including but not limited to fixed connections via structures such as slots or tenons, screws or rivets, welding, or adhesive bonding. The cavity 21a has an opening 21b and an opening 21c at opposite ends, respectively. The direction from opening 21b to opening 21c may be defined as a first direction.

[0043] As shown in Figures 2 and 3, the cavity 21a enclosed by the sidewalls 21 can illustratively be square. The sidewalls 21 can include four walls connected end to end, which can be referred to as a first wall 211, a second wall 212, a base plate 213, and a third wall 216. The first wall 211 is opposite the base plate 213, and the second wall 212 is opposite the third wall 216. Schematically, the second wall 212 and the third wall 216 can be longer, while the first wall 211 and the base plate 213 can be shorter. One end of the second wall 212 can extend beyond the edges of the first wall 211 and the base plate 213, and one end of the third wall 216 can extend beyond the edges of the first wall 211 and the base plate 213. In other embodiments, the cavity 21a enclosed by the sidewalls 21 is not limited to a square shape and can also be circular or elliptical. The number of walls of the sidewalls 21 is not limited to four and can be more or less. Schematically, the sidewalls 21 can also be a one-piece structure rather than a split structure.

[0044] As shown in FIG. 4 , a plurality of through holes 211 a may be provided on the first wall 211 , and one through hole 211 a is used for allowing one liquid-absorbing column 22 to pass through (to be described below).

[0045] In this embodiment, the first wall 211, the second wall 212, and the third wall 216 can be made of any material that can block the coolant. For example, the first wall 211, the second wall 212, and the third wall 216 can all be made of a metal material, such as copper. Copper can enhance convective heat transfer between the side wall 21 and the coolant, improving the heat transfer effect (convective heat transfer will be described further below).

[0046] As shown in Figures 3 and 4, the substrate 213 may include a base layer 214 and a wick 215, which may be stacked. The base layer 214 may face outward from the cavity 21a, and the wick 215 may face inward from the cavity 21a. The surface of the wick 215 facing away from the base layer 214 may serve as part of the inner surface of the sidewall 21. The shapes of the base layer 214 and the wick 215 may be designed based on the total amount of heat transfer and the heat flux density, and are not limited in the present embodiment.

[0047] As shown in Figure 5, schematically, a plurality of bosses 215a can be formed on the surface of the wick 215 facing away from the base layer 214, and each boss 215a can extend along the first direction. A groove 215b can be formed between any two adjacent bosses 215a, and the groove 215b can also extend along the first direction. Along the thickness direction of the wick 215, the groove 215b may not penetrate the wick 215. Schematically, the outermost boss 215a of the plurality of bosses 215a and the walls adjacent to the boss 215a can also form a groove 215b. For example, a groove 215b can be formed between the leftmost boss 215a and the third wall 216 in Figure 4, and a groove 215b can be formed between the rightmost boss 215a and the second wall 212 in Figure 4. In this embodiment, the shape, distribution position, and number of the bosses 215a are not limited, and the shape, distribution position, and number of the grooves 215b are not limited. For example, the grooves 215b may also penetrate the wick 215 along the thickness direction of the wick 215. In other embodiments, the bosses 215a and the grooves 215b may not be formed.

[0048] Illustratively, the base layer 214 can be made of a metal material with a high thermal conductivity. The wick 215 can be integrally formed on the base layer 214 using a metal powder sintering process. The metal powder forming the wick 215 can have, for example, a variety of particle sizes and / or shapes, or a single particle size and / or shape. In the case of multiple particle sizes and / or shapes, a mixed metal powder sintering process can be used.

[0049] FIG6 shows a schematic diagram of the microstructure of the wick 215. As shown in FIG6, a plurality of micropores are formed in the wick 215, so that the wick 215 can have a porous structure. The wick 215 can be a microscopic porous structure. Schematically, the pore size of the micropores can be about 100 nm to 200 nm, for example, 100 nm, 150 nm, 185 nm, 200 nm, etc. The pore size of these micropores can be inconsistent, with some micropores having a larger pore size and some micropores having a smaller pore size, so that the wick 215 has better adsorption performance for the coolant (described below). In other embodiments, the wick 215 or the entire substrate 213 with micropores can be manufactured by other materials and / or other processes, not limited to the above.

[0050] As shown in FIG5 , the wicking columns 22 in the heat sink 20 can be protruding from the top surfaces 215c of the plurality of bosses 215a. The top surfaces 215c are the surfaces of the bosses 215a facing away from the base layer 214. Each boss 215a can have a plurality of wicking columns 22 protruding from its top surface 215c. The number of wicking columns 22 on each boss 215a can be the same or different. Illustratively, each wicking column 22 can extend in a direction perpendicular to the top surface 215c, and the extension direction of the wicking columns 22 can be substantially perpendicular to the first direction.

[0051] Illustratively, the wicking columns 22 in the heat sink 20 can be arranged in a matrix, with the spacing between any two adjacent wicking columns 22 being equal. In other embodiments, the positions of the wicking columns 22 in the heat sink 20 can be designed as needed and are not limited to the above. For example, all wicking columns 22 can be located on the same wall, but not in a matrix arrangement; alternatively, all wicking columns 22 can be located on several walls, rather than being concentrated on the same wall.

[0052] As shown in Figures 5 and 7, each wick column 22 may include a heat dissipation rib 221 (which may be referred to as an array of needle ribs) and a wick 222 (for distinction, the wick 222 may be referred to as the first wick 222, and the wick 215 may be referred to as the second wick 215). It can be considered that the lower end of the heat dissipation rib 221 is connected to the top surface 215c of the boss 215a. The wick 222 may cover the outer peripheral surface of the heat dissipation rib 221, which is the surface surrounding the extension direction of the heat dissipation rib 221. The lower end of the wick 222 may be connected to the top surface 215c of the boss 215a. The upper end surface 222a of the wick 222 may be lower than the upper end surface 221a of the heat dissipation rib 221. That is, the distance from the upper end surface 222a of the wick 222 to the top surface 215c of the boss 215a may be smaller than the distance from the upper end surface 221a of the heat dissipation rib 221 to the top surface 215c of the boss 215a. Thus, a step 22c may be formed between the wick 222 and the heat dissipation rib 221.

[0053] In other embodiments, the upper end surface 222a of the wick 222 may be no lower than the upper end surface 221a of the heat dissipating rib 221. That is, the distance between the upper end surface 222a of the wick 222 and the top surface 215c of the boss 215a may be greater than or equal to the distance between the upper end surface 221a of the heat dissipating rib 221 and the top surface 215c of the boss 215a. When the upper end surface 222a of the wick 222 is higher than the upper end surface 221a of the heat dissipating rib 221, the portion of the wick 222 above the heat dissipating rib 221 may be solid, and the upper end surface 222a of the wick 222 may be closed and not grooved. Alternatively, the portion of the wick 222 above the heat dissipating rib 221 may be hollow, and the upper end surface 222a of the wick 222 may be provided with a groove. In addition, in this other embodiment, there may be no step 22c between the wick 222 and the heat dissipating rib 221.

[0054] In other embodiments, the lower end of the wick 222 may not be connected to the top surface 215c of the boss 215a, and a portion of the heat dissipation rib 221 may be exposed between the lower end of the wick 222 and the top surface 215c.

[0055] As shown in Figure 7, schematically, the surface of the wick 222 can form several grooves 222b (in order to distinguish, groove 222b can be referred to as the first groove 222b, and groove 215b can be referred to as the first groove 215b), and the number of grooves 222b is at least one. The extending direction of the grooves 222b can be roughly consistent with the extending direction of the wick column 22, and the grooves 222b can run through the wick 222 along the extending direction of the wick column 22. Schematically, these grooves 222b can include grooves 222b with two groove walls, and grooves 222b with three groove walls. In another embodiment, the number of groove walls of all grooves 222b can be the same, for example, two or three. In other embodiments, the surface of at least a portion of the wick 222 can be free of grooves 222b.

[0056] Illustratively, the heat dissipation ribs 221 can be made of a metal material with a high thermal conductivity. The wick 222 can be integrally formed on the heat dissipation ribs 221 using a metal powder sintering process. The metal powder forming the wick 222 can have, for example, a variety of particle sizes and / or shapes, or a single particle size and / or shape. In the case of multiple particle sizes and / or shapes, a mixed metal powder sintering process can be used.

[0057] With reference to shown in Figure 6, can form a plurality of micropores in the wick 222, so the wick 222 can have a porous structure. The wick 222 can have a microscopic porous structure. Schematically, the pore size of the micropore can be about 100nm to 200nm, for example 100nm, 150nm, 170nm, 200nm etc. The pore size of these micropores can be inconsistent, and the pore size of some micropores is larger, and the pore size of some micropores is smaller, so that the wick 222 has good adsorption performance (hereinafter will continue to explain) to cooling liquid. In other embodiments, the wick 222 or the whole wick column 22 with micropores can be manufactured by other materials and / or other processes, not limited to above.

[0058] In this embodiment, the substrate 213 and the liquid absorption column 22 can be connected as one, and can be manufactured in the following manner: an integrated structure of the base layer 214 and the heat dissipation ribs 221 (the integrated structure can be called an array needle fin heat exchange surface) can be manufactured through an integrated molding process, and the lower end of the heat dissipation rib 221 is connected to the surface of the base layer 214; then, through a metal powder mixed sintering process, connected liquid absorption cores 215 and liquid absorption cores 222 are formed on the integrated structure, the liquid absorption core 215 is connected to the base layer 214 as one, and the liquid absorption core 222 is connected to the heat dissipation ribs 221 as one, thereby manufacturing an integrated structure of the substrate 213 and the liquid absorption column 22.

[0059] As shown in conjunction with Figure 4 , in this embodiment, the upper end of each heat dissipating rib 221 can pass through a corresponding through-hole 211a in the first wall 211. The first wall 211 can be mounted on the step 22c between the wick 222 and the heat dissipating rib 221, and the first wall 211 can mate with the upper end surface 222a of the wick 222. As shown in conjunction with Figure 3 , the portion of the heat dissipating rib 221 located within the cavity 21a can be referred to as the first portion, and the portion that passes through the through-hole 211a and is exposed outside the cavity 21a can be referred to as the second portion. The wick 222 can be located within the cavity 21a and cover the outer periphery of the first portion.

[0060] It is understandable that the upper end of the heat dissipation rib 221 passes through the first wall 211, and the first wall 211 cooperates with the step 22c, which can increase assembly reliability, but this design is not necessary. In other embodiments, the positional relationship between the first wall 211 and the heat dissipation ribs 221 and the wick 222 may not be limited. For example, the first wall 211 may not be lower than the upper end surface 221a of the heat dissipation ribs 221, and the distance from the first wall 211 to the substrate 213 may be greater than or equal to the distance from the upper end surface 221a of the heat dissipation ribs 221 to the substrate 213, wherein there may be a step 22c or no step 22c between the wick 222 and the heat dissipation ribs 221, and the through hole 211a may not be provided on the first wall 211; and / or, the first wall 211 may not be higher than the upper end surface 222a of the wick 222, and the distance from the first wall 211 to the substrate 213 may be less than or equal to the distance from the upper end surface 222a of the wick 222 to the substrate 213, wherein there may be a step 22c or no step 22c between the wick 222 and the heat dissipation ribs 221.

[0061] As shown in Figure 3, in this embodiment, the second wall 212 and the third wall 216 can be connected to the two sides of the base plate 213, respectively. Thus, the first wall 211, the second wall 212, the base plate 213, and the third wall 216 can enclose a cavity 21a, which can also be referred to as a drainage channel (described below). A portion of the heat dissipating ribs 221 and the wick 222 can be located within the cavity 21a, while another portion (i.e., the upper end) of the heat dissipating ribs 221 can be exposed outside the cavity 21a.

[0062] In embodiments where the first wall 211 is not lower than the upper end surface 221a of the heat dissipating rib 221, the entire area of ​​the heat dissipating rib 221 can be located within the cavity 21a. In embodiments where the first wall 211 is lower than the upper end surface 222a of the wick 222, a portion of the wick 222 can be located within the cavity 21a, while another portion of the wick 222 can be exposed outside the cavity 21a.

[0063] Therefore, in summary, at least a portion of the liquid-absorbing column 22 in the embodiment of the present application can be located in the cavity 21 a.

[0064] The structure of the heat dissipation device 20 of this embodiment has been described in detail above. The working principle of the heat dissipation device 20 will be described below.

[0065] As shown in Figure 2, in an embodiment of the present application, the side of the substrate 213 of the heat dissipation device 20 facing away from the first wall 211 can be used to fix the heating device 40, and the heating device 40 and the wicking column 22 can be located on opposite sides of the substrate 213, respectively. Schematically, the heating device 40 and the substrate 213 can be connected by a thermal interface material, and the thermal interface material can reduce the contact thermal resistance. The thermal interface material can be provided on the base layer 214. The thermal interface material can be provided on the base layer 214 before the process of sintering the wick (the wick 215 and the wick 222 are collectively referred to as the wick); alternatively, the thermal interface material can be provided on the base layer 214 after the entire heat dissipation device 20 is manufactured.

[0066] Figures 1 and 8 illustrate the working state of the heat sink 20 in the electronic device 10. As shown in Figures 1 and 8, the heat sink 20 can be "standing" in the housing, that is, when the electronic device 10 is placed normally (excluding non-working states such as when the electronic device 10 is tilted or placed horizontally), the first direction from the opening 21b to the opening 21c can be roughly perpendicular to the ground. The heat sink 20 and the heating element 40 are both immersed in the coolant. The heat generated by the heating element 40 can be transferred to the side wall 21 (especially the substrate 213). The porous structure of the wick enables the wick to better absorb the coolant. The coolant absorbed by the wick absorbs heat and its temperature rises. After reaching the boiling point, it begins to boil, changing from a liquid phase to a gas phase and generating steam. The steam can rise upward in the cavity 21a, causing the coolant near the upward opening 21c to have a lower density (lower gaseous density) and the coolant near the downward opening 21b to have a higher density (higher liquid density). Due to the density difference between the two openings, the coolant can enter the cavity 21a through the downward opening 21b and flow out of the cavity 21a through the upward opening 21c, achieving convective heat transfer. Therefore, under the combined action of boiling heat absorption and convective heat transfer, the heat dissipation device 20 can effectively dissipate heat from the heating element.

[0067] In this embodiment, the cavity 21a can play a role in guiding the convection of the coolant, so the cavity 21a can also be called a drainage channel. The drainage channel is similar to a chimney and has a "chimney effect" (the temperature of the air inside the chimney increases due to heating, and the high-temperature air rises due to its low density and is discharged from the air outlet at the top of the chimney, which will form a low-pressure area inside the chimney; while the air temperature outside the chimney is relatively low, which is relatively a high-pressure area. In this way, there is a pressure difference between the inside and outside of the chimney, so that the air is continuously sucked in from the bottom of the chimney and discharged from the top of the chimney after being heated, forming a rapid convection of air. The chimney can construct a stable low-pressure area inside, sort out the relatively turbulent airflow, and make the airflow flow in an orderly and efficient manner, thereby enhancing heat convection), which can ensure that the coolant continuously flows from bottom to top through the wick, standardize the flow direction of the coolant, avoid interference from liquid flows in other directions, ensure the orderly circulation of the coolant, enhance convective heat exchange, and thus achieve efficient heat dissipation.

[0068] In this embodiment, the surfaces of the base layer 214 and the heat dissipation ribs 221 can be subjected to an enhanced boiling treatment through a metal powder sintering process to form wicks 215 and wicks 222 having micropores of various pore sizes. Wicks 215 and 222 can be said to have a multi-scale pore structure. Micropores with larger pore sizes facilitate rapid vapor escape, while micropores with smaller pore sizes facilitate coolant adsorption through capillary action. Thus, this porous structure with multiple pore sizes allows micropores of different pore sizes to work together, simultaneously achieving rapid vapor escape and on-demand distribution and replenishment of coolant. This effectively balances the conflicting issues between vapor escape and coolant absorption (steam escape requires a larger pore size, while capillary adsorption requires a smaller pore size), thereby enhancing the heat exchange efficiency of phase change heat transfer.

[0069] In this embodiment, by forming a liquid absorption core 215 on the base layer 214, forming a liquid absorption core 222 on the heat dissipation rib 221, and forming grooves 215b and grooves 222b, the adsorption area and the heat dissipation area can be expanded, thereby increasing the nucleation point (or vaporization nucleus, which refers to the tiny area or tiny cavity where bubbles are formed in the liquid, and is the starting point for bubble formation during the boiling process of the liquid. Tiny depressions, pores, cracks or impurities in the liquid or on the solid surface can become nucleation points because they can act as the core of the bubble and provide the space required for bubble growth), achieving boiling at low superheat (the coolant can boil at a lower temperature), and improving the boiling heat transfer coefficient, so that the heat dissipation of the heating device 40 can be timely and quickly.

[0070] As described above, the formation of wicks on both the base layer 214 and the heat dissipation ribs 221 can expand the heat dissipation area. It can be understood that in other embodiments, the wicks on the base layer 214 or the heat dissipation ribs 221 can be eliminated, and a certain heat dissipation area can be expanded to meet the heat dissipation needs in some scenarios.

[0071] The heat dissipation device 20 of the embodiment of the present application can spontaneously provide continuous circulation power for the coolant without the need for an external driving device to drive the coolant flow, thereby simplifying the heat dissipation design and reducing costs.

[0072] The solution of the embodiment of the present application can break through the upper limit of the traditional passive immersion liquid cooling heat dissipation density and can better meet the heat dissipation requirements of high heat flow electronic components. 2 It can work stably under high heat flux density of about 1000W.

[0073] While various embodiments of the present application have been described above, the above descriptions are illustrative, non-exhaustive, and not intended to be limiting of the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A heat dissipation device with immersion liquid cooling, characterized in that it includes a side wall and a plurality of liquid suction columns; the side wall encloses a cavity with openings at both ends; at least a part of each liquid suction column is located in the cavity, one end of each liquid suction column is connected to one side of the inner surface of the side wall, and each liquid suction column extends along the direction from one side of the inner surface to the other side opposite to the one side; each liquid suction column includes a porous structure.

2. The heat dissipation device according to claim 1, characterized in that each liquid suction column includes heat dissipation ribs and a first liquid suction core, the first liquid suction core covers the outer periphery of the heat dissipation ribs, and the first liquid suction core includes a porous structure.

3. The heat dissipation device according to claim 2, characterized in that a first groove is provided on the surface of the first liquid suction core of each liquid suction column, and the first groove extends along the extending direction of the liquid suction column.

4. The heat dissipation device according to any one of claims 1-3, characterized in that the side wall includes a base layer and a second liquid suction core, the base layer and the second liquid suction core are arranged in a laminated manner, the base layer is located on the side of the second liquid suction core away from the liquid suction column, and the second liquid suction core includes a porous structure; one end of each liquid suction column is connected to the surface of the second liquid suction core away from the base layer.

5. The heat dissipation device according to claim 4, characterized in that the surface of the second liquid suction core away from the base layer includes a plurality of protrusions, and a second groove is formed between every two adjacent protrusions, and one end of the plurality of liquid suction columns is connected to the surface of the plurality of protrusions.

6. The heat dissipation device according to any one of claims 1-5, characterized in that the porous structure includes large pores and small pores, and the aperture of the large pores is larger than the aperture of the small pores.

7. The heat dissipation device according to any one of claims 1-6, characterized in that the aperture of the pores in the porous structure is 100nm - 200nm.

8. The heat dissipation device according to claim 2 or 3, characterized in that the side wall includes a plurality of through holes; a first part of each heat dissipation rib is located in the cavity, and a second part of each heat dissipation rib passes through one of the through holes and is exposed outside the cavity.

9. The heat dissipation device according to claim 8, characterized in that the first liquid suction core is located in the cavity, and the first liquid suction core covers the outer periphery of the first part of the heat dissipation rib.

10. The heat dissipation device according to any one of claims 1-9, characterized in that the side wall includes a first wall, a second wall, a substrate and a third wall, the first wall, the second wall, the substrate and the third wall are sequentially connected end to end to enclose the cavity, the first wall is opposite to the substrate, and the second wall is opposite to the third wall; one end of each liquid suction column is connected to the surface of the substrate facing the cavity.

11. The heat dissipation device according to claim 10, characterized in that the plurality of liquid suction columns are integrally connected with the substrate.

12. The heat dissipation device according to claim 2, 3, 8 or 9, characterized in that The first wick is manufactured by a metal powder sintering process.

13. An immersion liquid-cooled electronic device, characterized in that it includes a housing, a coolant, a heating device, and the heat dissipation device according to any one of claims 1-12; the coolant, the heating device, and the heat dissipation device are all housed in the housing, the heating device and the heat dissipation device are both immersed in the coolant, and the heating device is fixed on a side of the side wall away from the liquid absorption column.

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