Phase change type heat dissipation system

Abstract

The utility model relates to a phase change type heat radiation system, comprising a server cabinet unit which comprises a server cabinet and a plurality of heating elements arranged in the server cabinet; the heat exchange unit comprises a microstructure cold head and a heat exchanger; the microstructure cold head is attached to the heating element, and a gap between the microstructure cold head and the heating element is filled with a heat-conducting medium. A heat exchange cavity filled with a fluid working medium is formed in the micro-structure cold head; a working medium outlet pipeline of the micro-structure cold head is communicated with the heat exchanger; the working medium supply unit comprises a liquid storage tank and a driving element which are communicated in sequence; the working medium inlet end of the liquid storage tank communicates with the working medium outlet end of the heat exchanger through a pipeline, and the working medium outlet end of the driving element communicates with the working medium inlet end of the microstructure cold head through a pipeline. Compared with the prior art, the insulating fluid is used as a working medium, the electric leakage risk of a common water cooling system is avoided, meanwhile, the heat exchange coefficient of the working medium in a boiling state is increased through the heat dissipation mode of the micro-structure cold head, the heat removal efficiency of a heating element is remarkably improved, and the service life of the heating element is prolonged. The heat dissipation problem of the high-power device in the server unit is solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to server heat dissipation technical field, concretely relates to a phase change type heat dissipation system. BACKGROUND

[0002] As the basic IT equipment of data center, server is an important carrier of data storage, processing, conversion and mining. With the continuous growth of emerging technology demand for computing power, the power and heat flux density of server microprocessor increase. According to the international electronic manufacturing technology roadmap prediction, the heat flux density of future microprocessing system will climb to 1000W / cm 2 , and the server system will face great heat dissipation pressure.

[0003] The traditional data center adopts air cooling heat dissipation mode, and the initial construction cost is low, but the energy utilization rate is low and the noise influence is large. When high-power density large data center gradually becomes the mainstream, the conventional air cooling heat dissipation mode is difficult to meet the ultra-high heat dissipation demand of data center due to the low heat dissipation limit. Single-phase liquid cooling heat dissipation mode has higher heat exchange coefficient, but when facing high heat flux density, the power of pump needs to be continuously improved to cope with the heat dissipation pressure, which is not conducive to the demand of energy saving and emission reduction. UTILITY MODEL CONTENT

[0004] The utility model discloses a phase change type heat dissipation system, two-phase liquid cooling heat dissipation is an advanced heat dissipation technology, it utilizes latent heat of liquid working medium phase change to take away a large amount of heat, has the characteristics of high heat exchange coefficient and lower energy consumption, the system designed by the utility model uses insulating fluid as working medium, avoids the risk of general water cooling system leakage, and the heat dissipation mode of microstructure cold head promotes the heat exchange coefficient of working medium under the boiling state, significantly improves the heat removal efficiency of heating element, and solves the heat dissipation problem of high-power device in server unit.

[0005] The utility model discloses a phase change type heat dissipation system, two-phase liquid cooling heat dissipation is an advanced heat dissipation technology, it utilizes latent heat of liquid working medium phase change to take away a large amount of heat, has the characteristics of high heat exchange coefficient and lower energy consumption, the system designed by the utility model uses insulating fluid as working medium, avoids the risk of general water cooling system leakage, and the heat dissipation mode of microstructure cold head promotes the heat exchange coefficient of working medium under the boiling state, significantly improves the heat removal efficiency of heating element, and solves the heat dissipation problem of high-power device in server unit.

[0006] A phase change type heat dissipation system, comprising:

[0007] A server cabinet unit, comprising a server cabinet and a plurality of heating elements arranged in the server cabinet;

[0008] The heat exchange unit comprises a microstructure cold head and a heat exchanger; the microstructure cold head is attached to the heat generating element, and a gap between the two is filled with a heat conducting medium; the microstructure cold head is internally provided with a heat exchange cavity filled with a fluid working medium; a working medium outlet pipeline of the microstructure cold head is in communication with the heat exchanger; the heat exchange unit is arranged above the opposite position of the server cabinet unit; and the heat conducting medium can be a heat conducting paste, a liquid metal, a solid thermal interface material or solder.

[0009] The working medium supply unit comprises a liquid storage tank and a driving element in sequence communication; a working medium inlet end of the liquid storage tank is in communication with a working medium outlet end of the heat exchanger through a pipeline, and a working medium outlet end of the driving element is in communication with a working medium inlet end of the microstructure cold head through a pipeline.

[0010] Further, the server cabinet is provided with a plurality of server cabinet trays in the height direction; the server cabinet trays are placed with server mainboards; and the server mainboards are installed with heat generating elements. The fixing mode of the server cabinet tray is not limited in the utility model, and the server cabinet tray can be connected with the server cabinet through parallel sliding rails and the like, and the parallel sliding rails can facilitate the adjustment of the position of the server cabinet tray in the server cabinet.

[0011] Optionally, a cooling fan is arranged on the top of the server cabinet to blow the gas in the server out of the top of the cabinet, so as to promote the circulation of the air flow in the cabinet.

[0012] Optionally, the server mainboard is installed in a server case, and the size of the server case combined with the server mainboard can be 1U, 2U or multiple U.

[0013] Preferably, the heat generating element is embedded on the server mainboard in the form of buckling or clamping. It should be noted that the specific type of the heat generating element is not limited, and the heat generating element can be a CPU, a GPU or a chip and the like.

[0014] Further, the heat conducting paste is a heat conducting silicone grease, the cost of which is low and there is no risk of electric conduction; the liquid metal is an alloy of gallium, indium, tin, bismuth and antimony metal elements, which can remain in a liquid state at room temperature; the solid thermal interface material is selected from one of a heat conducting pad, a metal soft pad and a thermal interface film; and the material of the solder is a low melting point metal material.

[0015] Still further, when the heat conducting medium is selected from a heat conducting paste, a liquid metal or a solid thermal interface material, the microstructure cold head is fixed above the heat generating element in the form of screw connection or buckling, and the surface attachment of the microstructure cold head and the heat generating element is realized through the pre-tightening force of the fastener.

[0016] Further, when the heat-conducting medium is liquid metal, a sealing device is added around the bonding interface between the microstructure cold head and the heat-generating element to prevent leakage of the liquid metal. The application does not limit the sealing device, and exemplarily, a high-temperature-resistant fluorine rubber O-ring can be used around the bonding interface between the microstructure cold head and the heat-generating element to realize sealing under the pre-tightening force of threaded connection or buckling.

[0017] Further, when the heat-conducting medium is solder, the microstructure cold head and the heat-generating element are connected in an integrated structure by welding.

[0018] Further, one or both sides of the heat exchanger is provided with a cooling fan; when the cooling fans are installed in parallel on both sides of the heat dissipation surface of the heat exchanger, the directions of all the air outlets of the cooling fans are consistent.

[0019] Further, the number of the heat exchangers is one or more; when there are multiple heat exchangers, the multiple heat exchangers are connected in series as a whole.

[0020] Further, the liquid level gauge, pressure gauge and gas pressure relief valve are arranged on the liquid storage tank; and a filter is arranged on the pipeline between the liquid storage tank and the driving element. The liquid level gauge is used to detect the liquid level in the liquid storage tank to avoid the risk of insufficient working fluid; the pressure gauge is used to detect the system pressure; after filling the working fluid medium, the air in the working fluid circulation system is discharged through the vacuum pump connected by the stop valve; the gas pressure relief valve is used to prevent excessive pressure in the pipe caused by boiling; and the working fluid is selected from one of nanofluid, fluorine-containing compound and ultrapure water.

[0021] Further, a flow meter is arranged on the pipeline between the driving element and the microstructure cold head.

[0022] Further, the working fluid outlet end of the microstructure cold head is connected to the heat exchanger through a working fluid outlet channel; when the number of the microstructure cold heads is multiple, the working fluid outlet channels connected to the working fluid outlet ends of the multiple microstructure cold heads are connected in parallel and then connected to the heat exchanger, and the working fluid inlet channels connected to the working fluid inlet ends of the microstructure cold heads are also connected in parallel and then connected to the driving element.

[0023] Further, the microstructure cold head is connected to the working fluid inlet channel and the working fluid outlet channel through a stainless steel tower joint, a stainless steel thread or a quick connector.

[0024] Further, the driving element includes one of a gear pump, a centrifugal pump, a plunger pump or a vane pump.

[0025] Preferably, the heat exchange unit and the working fluid supply unit are arranged above or below the opposite positions of the server cabinet unit; the working fluid enters the microstructure cold head through the working fluid inlet channel, the working fluid is boiled and heat-exchanged through the microstructure cold head, the heat of the heat generating element is taken away and the working fluid is converted into a two-phase state containing a large number of steam bubbles, and the two-phase working fluid enters the heat exchange unit through the working fluid outlet channel and returns to the working fluid supply unit after condensation, thereby forming a phase-change heat dissipation cycle of the working fluid.

[0026] Further, the heat exchange unit and the working fluid supply unit are integrated in a box, and the box is placed at the highest position of the server cabinet.

[0027] Compared with the prior art, the utility model has the following advantages:

[0028] (1) The utility model discloses an insulation fluid as working fluid, avoids the risk of general water cooling system leakage, and promotes the heat exchange coefficient of working fluid in the boiling state through the heat dissipation mode of the microstructure cold head, thereby significantly improving the heat removal efficiency of the heat generating element and solving the heat dissipation problem of high-power devices in the server unit.

[0029] (2) The utility model discloses a circulating heat dissipation system composed of a microstructure cold head, a heat exchange unit and a working fluid supply unit through necessary devices, and the two-phase boiling heat exchange has excellent heat dissipation capacity, so that the heat dissipation circulation needs of the whole cabinet system can be met without using high-power heat dissipation devices, the system energy consumption is greatly reduced while the structure is compact. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is one of the overall schematic views of the phase-change circulating heat dissipation system in the embodiment.

[0031] Figure 2 It is the second overall schematic view of the phase-change circulating heat dissipation system in the embodiment.

[0032] Figure 3 It is the schematic view of the relative position of the functional units of the phase-change circulating heat dissipation system in embodiment 1.

[0033] Figure 4 It is another schematic view of the relative position of the functional units of the phase-change circulating heat dissipation system in embodiment 1.

[0034] Figure 5 It is the schematic view of the box structure of the phase-change circulating heat dissipation system in embodiment 2.

[0035] The symbols in the figure are shown as follows:

[0036] 1-server cabinet unit; 11-server cabinet; 12-server cabinet tray; 13-server mainboard; 14-heat generating element; 15-microstructure cold head;

[0037] 2 - heat exchange unit; 21 - heat exchanger; 22 - heat dissipation fan;

[0038] 3 - working medium supply unit; 31 - liquid storage tank; 32 - pressure gauge; 33 - stop valve; 34 - filter; 35 - driving element; 36 - flow meter; 37 - working medium inlet channel; 38 - working medium outlet channel; 39 - circulating loop stop valve. DETAILED DESCRIPTION

[0039] The utility model will be explained in detail below in combination with the drawings and specific embodiments. The embodiments are implemented on the premise of the technical scheme of the utility model, and detailed implementation modes and specific operation processes are given, but the protection scope of the utility model is not limited to the following embodiments.

[0040] A phase change type heat dissipation system comprises:

[0041] A server cabinet unit 1 comprises a server cabinet 11 and heat generating elements 14 arranged uniformly in the server cabinet 11 along the height direction;

[0042] A heat exchange unit 2 comprises a microstructure cold head 15 and a heat exchanger 21; the microstructure cold head 15 is attached to the heat generating elements 14, and a gap between the two is filled with a heat conducting medium; the microstructure cold head 15 is internally provided with a heat exchange cavity filled with a fluid working medium; a working medium outlet pipeline of the microstructure cold head 15 is in communication with the heat exchanger 21;

[0043] A working medium supply unit 3 comprises a liquid storage tank 31 and a driving element 35 in sequence; a working medium inlet end of the liquid storage tank 31 is in communication with a working medium outlet end of the heat exchanger 21 through a pipeline, and a working medium outlet end of the driving element 35 is in communication with a working medium inlet end of the microstructure cold head 15 through a pipeline.

[0044] In some embodiments of the utility model, the server cabinet 11 is provided with multiple layers of server cabinet trays 12 along the height direction; the server cabinet trays 12 are placed with server mainboards 13; and the heat generating elements 14 are installed on the server mainboards 13.

[0045] In some embodiments of the utility model, the heat exchanger 21 is provided with heat dissipation fans 22 on one side or both sides; when the heat dissipation fans 22 are installed in parallel on both sides of the heat dissipation surface of the heat exchanger 21, the directions of all the air outlets of the heat dissipation fans 22 are kept consistent.

[0046] In some embodiments of the utility model, the number of the heat exchangers 21 is one or more; when there are multiple heat exchangers 21, the multiple heat exchangers 21 are connected in series to form a whole.

[0047] In some embodiments of the utility model, the liquid level gauge, pressure gauge 32 are provided on the liquid storage tank 31, the filter 34 is provided on the pipeline between the liquid storage tank 31 and the driving element 35.

[0048] In some embodiments of the utility model, the flow meter 36 is provided on the pipeline between the driving element 35 and the microstructure cold head 15.

[0049] In some embodiments of the utility model, the microstructure cold head 15 is communicated with the heat exchanger 21 through the working medium outlet channel 38, when the number of microstructure cold head 15 is multiple, the working medium outlet channel 38 communicated by the working medium outlet end of multiple microstructure cold head 15 is connected in parallel and then communicated with the heat exchanger 21, and the working medium inlet channel 37 communicated by the working medium inlet end of microstructure cold head 15 is also connected in parallel and then communicated with the driving element 35.

[0050] In some embodiments of the utility model, the microstructure cold head 15 is connected through stainless steel tower joint, stainless steel thread or quick connector between the working medium inlet channel 37 and the working medium outlet channel 38.

[0051] In some embodiments of the utility model, the driving element includes one of gear pump, centrifugal pump, plunger pump or vane pump.

[0052] In some embodiments of the utility model, the heat exchange unit 2 and the working medium supply unit 3 are integrated in the box body 4, and the box body 4 is placed at the highest position of the server cabinet 11.

[0053] In some embodiments of the utility model, the heat exchange unit 2 and the working medium supply unit 3 are integrated in the box body 4, and the box body 4 is placed at the lowest position of the server cabinet 11.

[0054] Embodiment 1

[0055] Please refer to Figures 1-4 The heat dissipation system of the embodiment includes: server cabinet unit 1, heat exchange unit 2 and working medium supply unit 3; the server cabinet tray 12 is arranged in the server cabinet unit 1; the server mainboard 13 is placed on the server cabinet tray 12; the microstructure cold head 15 is closely attached to the heating element 14 on the server mainboard 13, and the circulation of cold and hot working medium is realized through the working medium inlet channel 37 and the working medium outlet channel 38; the heat exchange unit 2 is communicated with the working medium outlet channel 38, and is used for condensing two-phase fluid working medium, and the heat exchange unit 2 is arranged above the opposite position of the server cabinet unit 1; the working medium supply unit 3 includes liquid storage tank 31, hydraulic pump 35 and auxiliary element, and is used for realizing stable working medium delivery to the microstructure cold head.

[0056] The server cabinet tray 12 is installed in parallel in the server cabinet 11. The embodiment does not limit the fixing mode of the tray. For example, the server cabinet tray 12 can be connected with the server cabinet 11 through parallel sliding rails or the like, which can facilitate the adjustment of the position of the server cabinet tray 12 in the server cabinet 11.

[0057] Optionally, a cooling fan is arranged at the top of the server cabinet 11 to blow the gas in the server out of the top of the cabinet, thereby promoting the circulation of the air flow in the cabinet.

[0058] Optionally, the server mainboard 13 is installed in a server case. The size of the server case in combination with the server mainboard 13 can be 1U, 2U or multiple U. By adjusting the parallel spacing of the server cabinet tray 12, server cases of different sizes can be placed.

[0059] The heat generating element 14 is embedded on the server mainboard 13 through buckling or clamping. It should be noted that the specific type of the heat generating element 14 is not limited. For example, the heat generating element 14 can be a CPU, a GPU or a chip, etc.

[0060] A heat-conducting medium is filled between the microstructure cold head 15 and the surface of the heat generating element 14. The heat-conducting medium can be a heat-conducting paste, a liquid metal, a solid thermal interface material or a solder. The heat-conducting paste is a heat-conducting silicone grease, which has low cost and no risk of electric conduction. The liquid metal is an alloy of gallium, indium, tin, bismuth and antimony, which can remain in a liquid state at room temperature. The solid thermal interface material is selected from one of a heat-conducting pad, a metal soft pad and a thermal interface film. The solder is a low-melting point metal material.

[0061] When the heat-conducting medium is selected from the heat-conducting paste, the liquid metal or the solid thermal interface material, the microstructure cold head 15 is fixed above the heat generating element 14 through screw connection or buckling, and the surface of the microstructure cold head 15 is attached to the heat generating element 14 by the pre-tightening force of the fastener.

[0062] When the heat-conducting medium is the liquid metal, a sealing device is added around the attachment interface between the microstructure cold head 15 and the heat generating element 14 to prevent leakage of the liquid metal. The application does not limit the sealing device. For example, a high-temperature-resistant fluorine rubber O-ring can be used around the attachment interface between the microstructure cold head 15 and the heat generating element 14 to realize sealing under the pre-tightening force of the screw connection or buckling. When the heat-conducting medium is the solder, the microstructure cold head 15 and the heat generating element 14 are connected in an integrated structure through welding.

[0063] The microstructure cold head 15 in the server cabinet unit 1 is communicated with the heat exchange unit 2 through the working medium outlet channel 38; when the number of the microstructure cold head 15 is multiple, the working medium outlet channels 38 connected with the outlets of the microstructure cold head 15 are connected in parallel and then connected with the heat exchange unit 2, and the working medium inlet channels 37 connected with the inlets of the microstructure cold head 15 are connected in parallel and then connected with the working medium supply unit 3.

[0064] The connection mode of the microstructure cold head 15 with the working medium inlet channel 37 and the working medium outlet channel 38 is selected from one of a stainless steel tower joint connection, a stainless steel threaded joint and a quick joint connection.

[0065] The heat exchange unit 2 comprises a heat exchanger 21 and a heat dissipation fan 22; the number of the heat exchanger 21 can be multiple; when the number of the heat exchanger 21 is multiple, the heat exchangers 21 are connected in series.

[0066] The heat dissipation fan 22 is installed in parallel on one side or both sides of the heat dissipation surface of the heat exchanger 21, so as to realize the condensation of the two-phase fluid in the condenser 21; when the heat dissipation fan 22 is installed in parallel on both sides of the heat dissipation surface of the condenser 21, the directions of the air outlets of the heat dissipation fan 22 are consistent.

[0067] The working medium supply unit 3 comprises a liquid storage tank 31, a pressure gauge 32, a stop valve 33, a filter 34, a hydraulic pump 35, a flow meter 36, a working medium inlet channel 37 and a working medium outlet channel 38; the filter 34 is provided with a circulating loop stop valve 39.

[0068] The liquid storage tank 31 is provided with a liquid level meter; the pressure gauge 32 is a vacuum pressure gauge; the type of the filter 34 is matched with the diameter of the working medium flow pipeline; the hydraulic pump 35 is selected from one of a gear pump, a centrifugal pump, a plunger pump and a vane pump.

[0069] The pressure gauge 32 is used to detect the system pressure; after the working fluid medium is filled, the air in the working medium circulation system is discharged through the stop valve 33 connected with a vacuum pump; the working fluid is selected from one of a nanofluid, a fluorine-containing compound and ultrapure water; when the working fluid is the ultrapure water, an additional water purification device is needed to avoid the impurities mixed in the ultrapure water to make the working fluid conductive.

[0070] The heat exchange unit 2 and the working medium supply unit 3 are arranged above or below the opposite positions of the server cabinet unit 1; the working fluid enters the microstructure cold head 15 through the working medium inlet channel 37, the working fluid is boiled and heat exchanged through the microstructure cold head 15, the heat of the heating element 14 is taken away and the working fluid is converted into a two-phase state containing a large number of steam bubbles, the two-phase working fluid enters the heat exchange unit 2 through the working medium outlet channel 38, is condensed and then returns to the working medium supply unit 3, so as to form a phase change type heat dissipation cycle of the working fluid.

[0071] Embodiment 2

[0072] As Figure 5 shown, the difference between this embodiment and embodiment 1 is that the main devices of the heat exchange unit 2 and the working medium supply unit 3 in this embodiment are built in a box 4, which can be a metal box. This structure arrangement can directly place the whole system in the server cabinet 1, improving the compatibility of the circulating cooling system and the server cabinet. Alternatively, the box 4 is placed at the highest position or the lowest position in the server cabinet 1.

[0073] The above is only a preferred embodiment of the present application, and is not intended to limit the present application in other forms. Any skilled person in the art can modify or change the above disclosed technology content to equivalent embodiments. However, any simple modification, equivalent change and modification made to the above embodiments without departing from the technical solution of the present application, according to the technical essence of the present application, still belongs to the protection scope of the technical solution of the present application.

Claims

1. A phase change heat dissipation system, characterized in that, The application relates to a server cabinet unit (1) comprising a server cabinet (11) and a plurality of heat generating elements (14) arranged in the server cabinet (11); a heat exchange unit (2) comprising a microstructure cold head (15) and a heat exchanger (21); the microstructure cold head (15) is in close contact with the heat generating elements (14), and a gap between the two is filled with a heat conducting medium; the microstructure cold head (15) is internally provided with a heat exchange cavity filled with a working fluid; a working fluid outlet pipeline of the microstructure cold head (15) is in communication with the heat exchanger (21); a working fluid supply unit (3) comprising a liquid storage tank (31) and a driving element (35) in sequence; a working fluid inlet end of the liquid storage tank (31) is in communication with a working fluid outlet end of the heat exchanger (21) through a pipeline, and a working fluid outlet end of the driving element (35) is in communication with a working fluid inlet end of the microstructure cold head (15) through a pipeline; the working fluid outlet end of the microstructure cold head (15) is in communication with the heat exchanger (21) through a working fluid outlet channel (38); when the number of the microstructure cold heads (15) is plural, the working fluid outlet channels (38) connected with the working fluid outlet ends of the plural microstructure cold heads (15) are connected in parallel and then communicated with the heat exchanger (21), and the working fluid inlet channels (37) connected with the working fluid inlet ends of the microstructure cold heads (15) are also connected in parallel and then communicated with the driving element (35); the heat exchange unit (2) and the working fluid supply unit (3) are arranged above or below the server cabinet unit (1) in opposite positions; working fluid enters the microstructure cold head (15) through the working fluid inlet channel (37), boiling heat exchange occurs in the working fluid through the microstructure cold head (15), the heat of the heat generating elements (14) is taken away, and the working fluid is converted into a two-phase state containing a large number of steam bubbles, the two-phase working fluid enters the heat exchange unit (2) through the working fluid outlet channel (38), is condensed and then returns to the working fluid supply unit (3), and a phase change type heat dissipation cycle of the working fluid is formed. The server cabinet (11) is provided with a plurality of server cabinet trays (12) in the height direction; the server cabinet trays (12) are placed with server mainboards (13); the server mainboards (13) are provided with heat generating elements (14); and the heat generating elements (14) are selected from one or more of a CPU, a GPU and a chip. One side or both sides of the heat exchanger (21) are provided with heat dissipation fans (22); when the heat dissipation fans (22) are parallelly arranged on both sides of the heat dissipation surface of the heat exchanger (21), the directions of the air outlets of all the heat dissipation fans (22) are consistent. The number of the heat exchangers (21) is one or more; when there are a plurality of heat exchangers (21), the plurality of heat exchangers (21) are connected in series to form a whole. The liquid storage tank (31) is provided with a liquid level meter, a pressure gauge (32) and a gas pressure relief valve; and a filter (34) is arranged on the pipeline between the liquid storage tank (31) and the driving element (35). A flow meter (36) is arranged on the pipeline between the driving element (35) and the microstructure cold head (15).

2. The phase change heat dissipation system of claim 1, wherein, ​ 3. The phase change heat dissipation system of claim 1, wherein, ​ 4. The phase change heat dissipation system of claim 1, wherein, ​ 5. The phase change heat dissipation system of claim 1, wherein, ​ 6. The phase change heat dissipation system of claim 1, wherein, ​ 7. The phase change heat dissipation system of claim 1, wherein, The microstructure cold head (15) is connected with the working medium inlet channel (37) and the working medium outlet channel (38) through a stainless steel tower joint, a stainless steel thread or a quick joint.

8. The phase change heat dissipation system of claim 1, wherein, The heat exchange unit (2) and the working medium supply unit (3) are integrated in a box (4), and the box (4) is placed at the highest position of the server cabinet (11).

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