Miniature liquid cooling circuit system and control method thereof

Abstract

The application relates to the technical field of computer heat dissipation, and provides a micro liquid cooling loop system and a control method thereof. The micro liquid cooling loop system comprises a circulating pump, a preheater, an evaporator assembly and a condenser, and the elements are connected through pipelines to form a liquid cooling loop; the circulating pump provides power for the flow of working medium in the whole liquid cooling loop, sends the working medium to the preheater, the preheater heats the working medium required to enter the evaporator assembly to a saturated state, in the evaporator assembly, the saturated working medium is continuously heated under the action of the heat of a board card, thereby generating gaseous working medium, so that the purpose of absorbing the heat of the board card is achieved, and after the gaseous working medium reaches the condenser, the gaseous working medium is cooled to become liquid working medium, and the next cycle is started. The working medium is heated to a saturated state through the preheater, the working medium is evaporated to absorb heat in the evaporator, the two-phase property of the working medium is utilized, the temperature control of the board card is realized, the heat dissipation effect is good, and the noise during the system operation is small.

Description

Technical Field

[0001] This invention relates to the field of computer heat dissipation technology, and in particular to a miniature liquid cooling circuit system and its control method. Background Technology

[0002] With the increasing complexity of electronic information systems and the promotion and application of new technologies such as high-performance cluster computing, large-capacity data storage, and high-bandwidth network switching, modern electronic devices are increasingly becoming highly integrated systems formed by high-density assembly and micro-assembly. The increase in heat flux density has put forward new demands on the heat dissipation capabilities of computers.

[0003] In domestically developed and controllable computers, high-performance, multi-core chips are widely used. The heat flux density of these chips is increasing, and the heat output of the entire system has risen from over 100 watts to over 500 watts. While traditional air cooling technology is simple in structure, low in cost, and highly reliable, it becomes very bulky, noisy, and ineffective when the chassis has high heat dissipation and concentrated heat.

[0004] Statistics show that over 55% of electronic product failures are caused by poor cooling system design. Excessively high operating temperatures not only reduce chip stability and increase error rates, but the thermal stress generated between the module's internal components and the external environment also directly affects the chip's operating frequency, mechanical strength, electrical performance, and reliability.

[0005] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this technical field. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a miniature liquid cooling circuit system and its control method, which solves the problems of high noise and poor heat dissipation effect of traditional heat dissipation systems, which in turn affect the chip's operating frequency, mechanical strength and other parameters, and increase the probability of chip failure.

[0007] In a first aspect, the present invention provides a miniature liquid cooling circuit system, the miniature liquid cooling circuit system comprising a circulating pump 1, a preheater 2, an evaporator assembly 3, and a condenser 4, wherein:

[0008] The outlet end of the circulating pump 1 and the inlet end of the preheater 2 are connected by a pipe. The outlet end of the preheater 2 and the inlet end of the evaporator assembly 3 are connected by a pipe. The outlet end of the evaporator assembly 3 and the inlet end of the condenser 4 are connected by a pipe. The inlet end of the circulating pump 1 and the outlet end of the condenser 4 are connected by a pipe to form a liquid cooling circuit. The evaporator assembly 3 is used for coupling with the circuit board.

[0009] The circulating pump 1 is used to provide power for the working fluid in the liquid cooling circuit, and the preheater 2 is used to heat the liquid working fluid to a saturated state, wherein the saturated working fluid flows into the evaporator assembly 3;

[0010] The evaporator assembly 3 is used to absorb the heat generated when the circuit board is working, so as to control the temperature of the circuit board; the condenser 4 is used to cool the working fluid flowing out from the evaporator assembly 3, forming a liquid working fluid, which then re-enters the circulation pump 1.

[0011] Furthermore, the micro liquid cooling circuit system also includes a regenerator 5, which includes a first port, a second port, a third port, and a fourth port. The first port and the second port form a flow channel, and the third port and the fourth port form a flow channel, wherein:

[0012] The first port is connected to the outlet of the circulating pump 1, the second port is connected to the inlet of the preheater 2, the third port is connected to the outlet of the evaporator assembly 3, and the fourth port is connected to the inlet of the condenser 4.

[0013] The regenerator 5 is used to heat the liquid working fluid from the circulating pump 1 using the saturated working fluid from the evaporator assembly 3.

[0014] Furthermore, the micro liquid cooling circuit system also includes a liquid reservoir 6, which is installed on the pipeline between the condenser 4 and the circulating pump 1, and is suitable for providing or storing working fluid during the operation of the micro liquid cooling circuit system.

[0015] Furthermore, a heater is provided inside the liquid reservoir 6, which is suitable for controlling the saturation pressure and saturation temperature of the working fluid inside the liquid reservoir 6, thereby realizing the control of the saturation temperature of the working fluid inside the evaporator assembly 3.

[0016] Furthermore, the micro liquid cooling circuit system also includes a filter 7, which is disposed on the pipeline between the condenser 4 and the circulating pump 1 and is suitable for filtering the working fluid.

[0017] Furthermore, the evaporator assembly 3 includes multiple evaporator units 31, and each evaporator unit 31 is provided with a disconnector 33 at both its outlet and inlet ends. The disconnector 33 is suitable for controlling the entry and exit of the working fluid in the evaporator, thereby realizing the control of the working fluid flow between the evaporators.

[0018] Furthermore, the evaporator assembly 3 is coupled to the board using a microchannel cold plate or a loop heat pipe 32.

[0019] Furthermore, the loop heat pipe 32 includes a flat tube 321, a shell 322, and a vapor chamber 323, wherein:

[0020] The flat tube 321 is a heat pipe formed by pressing a heat pipe body before it enters the evaporator. A shell 322 is welded on the top of the flat tube 321. The cavity formed between the shell 322 and the flat tube 321 is the steam chamber 323. The tube wall of the flat tube 321, which is wrapped by the shell 322, is provided with capillary pores 324. The capillary pores 324 are used to connect the steam chamber 323 and the flat tube 321 so that the gaseous working fluid can enter the steam chamber 323 from the flat tube 321. The flat tube 321 is used to provide a flow channel for the liquid working fluid.

[0021] Under the influence of the pore diameter of the capillary 324, the length of the capillary 324, and the steam pressure in the steam chamber 323, the liquid working fluid can only overflow through the capillary 324 to a preset height in the steam chamber 323, so that the liquid working fluid fills the flat tube 321.

[0022] Furthermore, the micro liquid cooling circuit system also includes multiple pressure sensors 8, wherein:

[0023] A pressure sensor 8 is installed on the pipe between the circulating pump 1 and the preheater 2, a pressure sensor 8 is installed on the pipe between the evaporator assembly 3 and the condenser 4, and a pressure sensor 8 is installed on the pipe between the condenser 4 and the circulating pump 1. The pressure sensor 8 is suitable for monitoring the pressure of pipes at various points in the micro liquid cooling circuit system.

[0024] Secondly, the present invention provides a control method for a micro liquid-cooled circuit system, the control method comprising:

[0025] The working state of the circulating pump 1 is controlled by the PLC control loop. The power of the circulating pump 1 is controlled according to the temperature of the card plate, and the flow rate and pressure of the working fluid entering the preheater 2 are controlled to change the subcooling of the system.

[0026] By controlling the saturation pressure and saturation temperature of the working fluid in the liquid reservoir 6, the saturation temperature and saturation pressure of the working fluid in the evaporator can be controlled.

[0027] By controlling the on / off state of the evaporator inlet disconnector 33, the flow rate of the working fluid between the evaporators can be controlled, thereby achieving precise temperature control of the circuit board.

[0028] In this embodiment of the invention, the circulating pump 1, preheater 2, evaporator assembly 3, and condenser 4 are connected by pipes to form a liquid cooling circuit. The evaporator assembly 3 is coupled to the circuit board. The circulating pump 1 provides power for the flow of the working fluid in the entire liquid cooling circuit, sending the working fluid to the preheater 2. The preheater 2 heats the working fluid to a saturated state before it enters the evaporator assembly 3. In the evaporator assembly 3, the saturated working fluid is further heated by the heat from the circuit board, evaporating to produce a gaseous working fluid, thus absorbing heat from the circuit board. The gaseous working fluid is cooled to a liquid state in the condenser 4, and then the next cycle begins. This embodiment of the invention utilizes the two-phase change of the working fluid by heating the working fluid to a saturated state in the preheater 2 and then evaporating and absorbing heat in the evaporator to achieve temperature control of the circuit board. The heat dissipation effect is good, and the system operates with low noise. It reduces the impact of thermal stress on the operating frequency, mechanical strength, and electrical performance of the chips on the circuit board, improves chip stability, and reduces the error rate. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0030] Figure 1 This is a schematic diagram of a micro liquid cooling circuit system provided in an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of another micro liquid cooling circuit system provided in an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of the loop heat pipe 32 of a micro liquid cooling loop system provided in an embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of the loop heat pipe 32 of another micro liquid cooling loop system provided in an embodiment of the present invention;

[0034] Figure 5 This is a schematic flowchart of a control method for a micro liquid cooling circuit system provided in an embodiment of the present invention;

[0035] Figure 6 This is a test wiring diagram of a miniature liquid cooling circuit system provided in an embodiment of the present invention.

[0036] The attached figures are labeled as follows: 1. Circulating pump; 2. Preheater; 3. Evaporator assembly; 31. Evaporator unit; 32. Loop heat pipe; 321. Flat tube; 322. Shell; 323. Steam chamber; 324. Capillary pore; 33. Connector; 4. Condenser; 5. Regenerator; 6. Liquid receiver; 7. Filter; 8. Pressure sensor. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0038] In the description of this invention, the terms "inner", "outer", "longitudinal", "lateral", "upper", "lower", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and do not require that this invention must be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0039] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] Example 1:

[0041] Embodiment 1 of the present invention provides a miniature liquid cooling circuit system, such as Figure 1 As shown, the micro liquid cooling loop system includes a circulating pump 1, a preheater 2, an evaporator assembly 3, and a condenser 4. The outlet end of the circulating pump 1 and the inlet end of the preheater 2 are connected by a pipe, the outlet end of the preheater 2 and the inlet end of the evaporator assembly 3 are connected by a pipe, the outlet end of the evaporator assembly 3 and the inlet end of the condenser 4 are connected by a pipe, and the inlet end of the circulating pump 1 and the outlet end of the condenser 4 are connected by a pipe to form a liquid cooling loop. The evaporator assembly 3 is used for coupling with a circuit board, wherein the circuit board is provided with chips.

[0042] The circulating pump 1 is used to provide power to the working fluid in the liquid cooling circuit, and the preheater 2 is used to heat the liquid working fluid to a saturated state, wherein the saturated working fluid flows into the evaporator assembly 3.

[0043] The evaporator assembly 3 is used to absorb the heat generated when the circuit board is working, so as to control the temperature of the circuit board; the condenser 4 is used to cool the working fluid flowing out from the evaporator assembly 3, forming a liquid working fluid, which then re-enters the circulation pump 1.

[0044] Among them, the saturated state is a state in which the liquid and gaseous states are in relative equilibrium. That is, the saturated working medium contains both liquid and gaseous working medium, and there are both liquid working medium changing into gaseous working medium and gaseous working medium changing into liquid working medium. The liquid and gaseous working medium are in a dynamic equilibrium.

[0045] When the working fluid enters the preheater 2, the preheater 2 heats the liquid working fluid to a saturated state. After the saturated working fluid flows into the evaporator assembly 3, the working fluid absorbs heat from the circuit board and is further heated. A portion of the liquid working fluid changes into a gaseous working fluid, and the mass fraction of the gaseous working fluid further increases. That is, during the process of the working fluid changing from liquid to gaseous, it absorbs heat from the circuit board, thereby achieving the purpose of controlling the temperature of the circuit board.

[0046] In a typical two-phase liquid cooling system, if the evaporation temperature of the working fluid is 40°C, then when the temperature of the circuit board exceeds 40°C, the working fluid will begin to evaporate rapidly after entering the evaporator assembly 3, absorbing the heat from the circuit board. Generally speaking, within a reasonable range, the lower the evaporation temperature of the working fluid, the easier it is to evaporate, and the better the heat dissipation effect.

[0047] In this embodiment, the advantage of using the preheater 2 to heat the working fluid to a saturated state is that it can convert the working fluid into a two-phase working fluid with liquid and gaseous working fluids before it enters the evaporator assembly 3. This allows the working fluid to quickly vaporize when it enters the evaporator assembly 3, thereby absorbing a large amount of heat generated by the circuit board, achieving temperature control of the circuit board, and enhancing the heat dissipation efficiency of the micro liquid cooling circuit system.

[0048] After the working fluid flows out of the evaporator assembly 3, it flows to the condenser 4, where the working fluid is cooled and the gaseous working fluid in the working fluid is converted into a liquid working fluid.

[0049] It should be noted that the micro liquid cooling circuit system may have multiple evaporator components 3, which are connected in series or in parallel in the pipes of the micro liquid cooling circuit system. Each evaporator component 3 can dissipate heat for one board or multiple boards.

[0050] In this embodiment of the invention, the circulating pump 1, preheater 2, evaporator assembly 3, and condenser 4 are connected by pipes to form a liquid cooling circuit. The evaporator assembly 3 is coupled to the circuit board. The circulating pump 1 provides power for the flow of the working fluid in the entire liquid cooling circuit, sending the working fluid to the preheater 2. The preheater 2 heats the working fluid to a saturated state before it enters the evaporator assembly 3. In the evaporator assembly 3, the saturated working fluid is further heated by the heat from the circuit board, evaporating to produce a gaseous working fluid, thus absorbing heat from the circuit board. The gaseous working fluid is cooled to a liquid state in the condenser 4, and then the next cycle begins. This embodiment of the invention utilizes the two-phase change of the working fluid by heating the working fluid to a saturated state in the preheater 2 and evaporating it in the evaporator to absorb heat, achieving temperature control of the circuit board. The heat dissipation effect is good, and the system operates with low noise. It reduces the impact of thermal stress on the operating frequency, mechanical strength, and electrical performance of the chips on the circuit board, improving chip stability and reducing error rate.

[0051] In order to utilize the waste heat of the system, the micro liquid cooling loop system also includes a regenerator 5, which includes a first port, a second port, a third port and a fourth port. The first port and the second port form a flow channel, and the third port and the fourth port form a flow channel.

[0052] The first port is connected to the outlet of the circulating pump 1, the second port is connected to the inlet of the preheater 2, the third port is connected to the outlet of the evaporator assembly 3, and the fourth port is connected to the inlet of the condenser 4.

[0053] The regenerator 5 is used to heat the liquid working fluid from the circulating pump 1 using the saturated working fluid from the evaporator assembly 3.

[0054] The flow channels formed by the first port and the second port, and the flow channels formed by the third port and the fourth port, are not interconnected.

[0055] like Figure 2 As shown, the working fluid in the evaporator assembly 3 enters the regenerator 5 through the third port, and then flows out through the fourth port to the condenser 4 for cooling. The circulating pump 1 first delivers the working fluid to the regenerator 5 through the first port. The working fluid output from the circulating pump 1 exchanges heat with the working fluid flowing out of the evaporator assembly 3 in the regenerator 5. That is, the working fluid output from the circulating pump 1 is heated by the working fluid flowing out of the evaporator assembly 3 in the regenerator 5, and then flows out through the second port and flows to the preheater 2 to be heated to saturation.

[0056] To control the mass of the components participating in the entire heat dissipation cycle in the micro liquid cooling circuit system, the micro liquid cooling circuit system also includes a liquid reservoir 6, such as... Figure 2 As shown, the liquid reservoir 6 is installed on the pipeline between the condenser 4 and the circulating pump 1, and is suitable for providing or storing working fluid during the operation of the micro liquid cooling circuit system.

[0057] Specifically, the outlet of the condenser 4 and the inlet of the liquid reservoir 6 are connected by a pipe, and the outlet of the liquid reservoir 6 and the inlet of the circulating pump 1 are connected by a pipe. When the operating conditions of the micro liquid cooling circuit system change, the phase change of the working fluid will cause a significant change in the volume of the working fluid. At this time, the liquid reservoir 6 needs to accommodate excess working fluid or provide the working fluid required for the normal operation of the micro liquid cooling circuit system. For example, when the temperature of the circuit board decreases, the mass ratio of liquid working fluid in the entire micro liquid cooling circuit system increases, and the liquid reservoir can store excess liquid working fluid.

[0058] In order to improve the heat dissipation effect of the evaporator assembly 3, a heater is provided in the liquid reservoir 6, which is suitable for controlling the saturation pressure and saturation temperature of the working fluid in the liquid reservoir 6, thereby realizing the control of the saturation temperature of the working fluid in the evaporator assembly 3.

[0059] Specifically, the evaporator assembly 3 and the liquid receiver 6 are located in the same closed loop. The pressure and temperature of the entire system can be affected by controlling the pressure and temperature of the liquid receiver 6, thereby influencing the pressure and temperature of the working fluid within the evaporator assembly 3. Since the amount of working fluid and the space within the micro liquid cooling loop system are constant, the saturation pressure and saturation temperature of the working fluid within the liquid receiver 6 can be controlled, thereby achieving control over the saturation temperature and pressure of the working fluid within the evaporator.

[0060] The higher the saturation pressure of the working fluid, the easier it is to vaporize. The easier it is to vaporize, the better its heat absorption capacity. Therefore, the saturation pressure of the working fluid in the reservoir 6 can be determined based on the temperature of the plate. The saturation pressure of the working fluid in the evaporator can be controlled by controlling the saturation pressure of the working fluid in the reservoir 6.

[0061] The relationship between the saturated temperature difference and saturated pressure difference of the working fluid between the evaporator assembly 3 and the liquid receiver 6 can be expressed as:

[0062]

[0063] Among them, T E T is the saturation temperature of the working fluid inside evaporator assembly 3. A ΔP is the saturation temperature of the working fluid inside reservoir 6. EA The pressure difference between the saturation pressure of the working fluid in the evaporator assembly 3 and the saturation pressure of the working fluid in the reservoir 6. Saturation temperature TA Pressure-temperature slope value at a point.

[0064] To filter impurities in the working fluid and ensure the normal operation of the micro liquid cooling circuit system, the micro liquid cooling circuit system also includes a filter 7, such as... Figure 2 As shown, the filter 7 is installed on the pipeline between the condenser 4 and the circulating pump 1, and is suitable for filtering the working fluid.

[0065] During the circulation of the working fluid in the micro liquid cooling circuit system, impurities such as dirt will inevitably appear. In order to prevent these impurities from affecting components such as the circulation pump 1 during the circulation of the working fluid, a filter 7 is installed in the micro liquid cooling circuit system to filter the working fluid, ensuring the normal use of the micro liquid cooling circuit system and extending its service life.

[0066] In order to achieve precise temperature control of the circuit board, the evaporator assembly 3 includes multiple evaporator units 31. Each evaporator unit 31 is provided with a disconnector 33 at both its outlet and inlet ends. The disconnector 33 is used to control the flow of the working fluid into and out of the evaporator unit 31, thereby realizing the flow control of the working fluid between the evaporator units 31.

[0067] An evaporator assembly 3 contains multiple evaporator units 31, which can dissipate heat for one or more circuit boards. In order to more accurately control the temperature of each circuit board, each evaporator unit 31 is equipped with a disconnector 33 at its inlet end to control whether the working fluid can enter the corresponding evaporator unit 31, thereby realizing the working fluid flow control of the evaporator units 31 between different circuit boards, and thus increasing or decreasing the heat dissipation support of the corresponding circuit boards.

[0068] Specifically, when multiple evaporator units 31 provide heat dissipation support for a target board, and the temperature of the target board is significantly lower than the temperatures of other boards, the working fluid flow rate of the evaporator unit 31 providing heat dissipation support to the target board can be reduced by shutting down the disconnectors 33 corresponding to one or more evaporator units 31 providing heat dissipation support to the target board, and the working fluid flow rate of the evaporator unit 31 providing heat dissipation support to other boards can be increased, thereby reducing the heat dissipation support for the target board and enhancing the heat dissipation support for other boards, so as to achieve the purpose of precise temperature control for each board.

[0069] In an optional embodiment, a flow valve is installed at the inlet end of the evaporator unit 31, which can also control the flow rate of the working fluid between each evaporator unit 31, thereby achieving precise temperature control of different boards.

[0070] To improve the heat dissipation effect of the micro liquid cooling circuit system, the evaporator assembly 3 is coupled to the board using a microchannel cold plate or a loop heat pipe 32.

[0071] The advantage of coupling the evaporator assembly 3 with the circuit board using a microchannel cold plate or loop heat pipe 32 is that it can increase the contact surface between the evaporator assembly 3 and the circuit board, allowing more working fluid to absorb heat from the circuit board simultaneously, thereby enhancing the heat dissipation effect of the evaporator assembly 3.

[0072] To further improve the heat dissipation effect of the micro liquid cooling circuit system, such as Figure 3 and Figure 4 As shown, the loop heat pipe 32 includes a flat tube 321, a shell 322, and a vapor chamber 323. The flat tube 321 is a heat pipe formed by pressing a heat pipe body before it enters the evaporator unit 31. That is, the loop heat pipe of this embodiment is used in the evaporator unit 31. A shell 322 is provided on the top of the flat tube 321. That is, the shell 322 only wraps around the top of the flat tube 321. The cavity formed between the shell 322 and the flat tube 321 is the vapor chamber 323. The tube wall of the flat tube 321 wrapped by the shell 322 is provided with a plurality of capillary pores 324. The capillary pores 324 are distributed along the length direction of the flat tube 321 and are arranged in multiple rows. The capillary pores 324 are used to connect the vapor chamber 323 and the flat tube 321 so that the gaseous working fluid enters the vapor chamber 323 from the flat tube 321. The flat tube 321 is used to provide a flow channel for the liquid working fluid.

[0073] Under the influence of the pore diameter and length of the capillary pore 324 and the steam pressure in the steam chamber 323, the liquid working fluid can only overflow through the capillary pore 324 to a preset height in the steam chamber 323, so that more liquid working fluid fills the flat tube 321. In this way, the liquid and gaseous working fluids in the saturated working fluid can be separated to increase the contact surface between the liquid working fluid and the lower part of the flat tube 321, thereby increasing the heat dissipation area of ​​the circuit board.

[0074] Specifically, when the loop heat pipe 32 is attached to the circuit board, the lower part of the flat tube 321 is closer to the circuit board. The flat tube 321 can increase the contact surface between the liquid working fluid and the lower part of the flat tube 321. At the same time, the flat tube 321 has a vapor chamber 323 above it, which can accommodate the gaseous working fluid. The gaseous working fluid formed after the liquid working fluid absorbs heat and evaporates enters the vapor chamber 323 through the capillary pores 324 without occupying the flow space of the liquid working fluid in the flat tube 321. This allows the liquid working fluid to absorb heat and evaporate to the maximum extent when passing through the flat tube 321, thereby enhancing the heat dissipation capability of the evaporator assembly 3 for the circuit board. Because the pore size of the capillary 324 is small, and the pressure generated by the gaseous working fluid in the steam chamber 323, the liquid working fluid cannot enter the steam chamber 323 in large quantities. The liquid working fluid that does enter the steam chamber 323 will gradually evaporate and will not occupy the steam chamber 323 indefinitely. The gaseous working fluid in the steam chamber 323 flows out of the steam chamber 323 from the capillary 324 at the front end of the steam chamber 323 along the flow direction of the working fluid in the entire system.

[0075] To monitor the pressure of the micro liquid cooling circuit system, the micro liquid cooling circuit system also includes multiple pressure sensors 8, such as... Figure 2 As shown, a pressure sensor 8 is installed on the pipe between the circulating pump 1 and the preheater 2, a pressure sensor 8 is installed on the pipe between the evaporator assembly 3 and the condenser 4, and a pressure sensor 8 is installed on the pipe between the condenser 4 and the circulating pump 1. The pressure sensor 8 is suitable for monitoring the pressure of pipes at various points in the micro liquid cooling circuit system.

[0076] Among them, one pressure sensor 8 measures the pressure at the inlet of the circulating pump 1; one pressure sensor 8 measures the pressure at the outlet of the evaporator; and one pressure sensor 8 measures the pressure at the outlet of the circulating pump 1, specifically the pressure in the pipe between the regenerator 5 and the preheater 2.

[0077] The purpose of measuring the pressure in various pipes within the micro liquid cooling circuit system is to monitor whether the system is operating normally and to adjust the pressure in the pipes promptly based on any abnormalities, thus maintaining the normal operation of the system. For example, if the pipe pressure is too low, the power of the circulating pump 1 can be increased to allow the working fluid to flow normally in the circuit, ensuring the normal operation of the micro liquid cooling circuit system.

[0078] Example 2:

[0079] Embodiment 2 of the present invention provides a control method for a micro liquid cooling circuit system, which is applied to the micro liquid cooling circuit system shown in Embodiment 1, such as... Figure 5As shown, the control method includes:

[0080] Step 101: Control the working state of the circulating pump 1 through the PLC (Programmable Logic Controller) control loop, control the power of the circulating pump 1 according to the temperature of the card plate, control the flow rate and pressure of the working fluid entering the preheater 2, and change the subcooling of the system;

[0081] Step 102: By controlling the saturation pressure and saturation temperature of the working fluid in the liquid reservoir 6, the saturation temperature and saturation pressure of the working fluid in the evaporator assembly 3 are controlled.

[0082] Step 103: By controlling the on / off state of each heat dissipation channel of the evaporator assembly 3, the flow rate of the working fluid between each heat dissipation channel is controlled, thereby achieving precise temperature control of the circuit board.

[0083] Specifically, in step 101, when the board temperature rises and the heat dissipation efficiency is too low at the current power of the circulating pump 1, the power of the circulating pump 1 is increased, the flow rate of the working fluid entering the preheater 2 is increased, and the flow rate of the working fluid entering the evaporator is increased, thereby improving the heat dissipation effect of the micro liquid cooling circuit system.

[0084] In an optional configuration, the circuit board's temperature is divided into a temperature gradient, corresponding to the power gradient of the circulation pump 1. When the circuit board's temperature reaches a certain temperature gradient value, the power of the circulation pump 1 is adjusted to the corresponding power. For example, if the circuit board's operating temperature is 30℃ to 80℃, and the circulation pump 1 has three power levels, then when the circuit board's temperature is below 40℃, the circulation pump 1 uses the first power level; when the circuit board's temperature is between 40℃ and 60℃, the circulation pump 1 uses the second power level; and when the circuit board's temperature is above 60℃, the circulation pump 1 uses the third power level, where the third power level is greater than the second power level, and the second power level is greater than the first power level.

[0085] In a typical two-phase liquid cooling system, if the evaporation temperature of the working fluid is 40°C, then when the circuit board temperature exceeds 40°C, the working fluid will begin to evaporate rapidly after entering the evaporator assembly 3, absorbing the heat from the circuit board. Generally, within a reasonable range, the lower the evaporation temperature of the working fluid, the easier it is to evaporate, and the better the heat dissipation effect. In this embodiment, a preheater 2 is used to heat the working fluid. Its advantage is that it can convert the working fluid into a two-phase working fluid with both liquid and gaseous states before entering the evaporator. This allows the working fluid to rapidly vaporize upon entering the evaporator, thereby absorbing a large amount of heat generated by the circuit board, achieving temperature control of the circuit board, and ensuring the heat dissipation efficiency of the micro liquid cooling circuit system.

[0086] In step 102, a heater is installed inside the liquid reservoir 6 to control the saturation pressure and saturation temperature of the working fluid inside the liquid reservoir 6, thereby controlling the saturation temperature and saturation pressure of the working fluid inside the evaporator. Specifically, the evaporator assembly 3 and the liquid reservoir 6 are located in the same closed loop. By controlling the pressure and temperature of the liquid reservoir 6, the pressure and temperature of the entire system can be affected, thereby affecting the pressure and temperature of the working fluid inside the evaporator assembly 3. Because the amount of working fluid in the micro liquid cooling circuit system is constant, and the space is also constant, the saturation temperature and saturation pressure of the working fluid inside the evaporator can be controlled by controlling the saturation pressure and saturation temperature of the working fluid inside the liquid reservoir 6.

[0087] The higher the saturation pressure of the working fluid, the easier it is to vaporize. The easier it is to vaporize, the better its heat absorption capacity. Therefore, the saturation pressure of the working fluid in the reservoir 6 can be determined based on the temperature of the plate. The saturation pressure of the working fluid in the evaporator can be controlled by controlling the saturation pressure of the working fluid in the reservoir 6.

[0088] In step 103, to achieve precise temperature control of the circuit board, the evaporator assembly 3 includes multiple evaporator units 31. Each evaporator unit 31 is equipped with a disconnector 33 at both its outlet and inlet ends. The disconnector 33 is used to control whether the working fluid can enter or exit the evaporator unit 31, thereby achieving working fluid flow control between the evaporator units 31. One evaporator unit 31 corresponds to one heat dissipation channel.

[0089] An evaporator assembly 3 contains multiple evaporator units 31, which can dissipate heat for one or more circuit boards. In order to more accurately control the temperature of each circuit board, each evaporator unit 31 is equipped with a disconnector 33 at its inlet end to control whether the working fluid can enter the corresponding evaporator unit 31, thereby realizing the working fluid flow control of the evaporator units 31 between different circuit boards, and thus increasing or decreasing the heat dissipation support of the corresponding circuit boards.

[0090] Specifically, when multiple evaporator units 31 provide heat dissipation support for a target board, and the temperature of the target board is significantly lower than the temperatures of other boards, the working fluid flow rate of the evaporator unit 31 providing heat dissipation support to the target board can be reduced by shutting down the disconnectors 33 corresponding to one or more evaporator units 31 providing heat dissipation support to the target board, and the working fluid flow rate of the evaporator unit 31 providing heat dissipation support to other boards can be increased, thereby reducing the heat dissipation support for the target board and enhancing the heat dissipation support for other boards, so as to achieve the purpose of precise temperature control for each board.

[0091] In this embodiment of the invention, the circulating pump 1, preheater 2, evaporator assembly 3, and condenser 4 are connected by pipes to form a liquid cooling circuit. The evaporator assembly 3 is coupled to the circuit board. The circulating pump 1 provides power for the flow of the working fluid in the entire liquid cooling circuit, sending the working fluid to the preheater 2. The preheater 2 heats the working fluid to a saturated state before it enters the evaporator assembly 3. In the evaporator assembly 3, the saturated working fluid is further heated by the heat from the circuit board, evaporating to form a large amount of gaseous working fluid, thus absorbing heat from the circuit board. The gaseous working fluid reaches the condenser 4 and is cooled to a liquid state, then the next cycle begins. This embodiment of the invention utilizes the two-phase change of the working fluid—heating the working fluid to a saturated state in the preheater 2 and absorbing heat through evaporation in the evaporator—to achieve temperature control of the circuit board, resulting in good heat dissipation and low noise during system operation.

[0092] Example 3:

[0093] Embodiment 3 of the present invention provides a test method for a micro liquid-cooled circuit system, which is applied to the micro liquid-cooled circuit system described in Embodiment 1, such as... Figure 6 As shown, the testing method includes: arranging multiple temperature measuring points from a multi-channel thermometer on the pipes of the miniature liquid cooling loop system to measure the temperature of the pipes; connecting a multi-point data acquisition instrument to the pressure sensor 8 on the miniature liquid cooling loop system to obtain the pressure of the pipes; determining whether the miniature liquid cooling loop system is working properly based on the measured temperature and pressure data; and testing the operating status of the miniature liquid cooling loop system under different power conditions of the circulating pump 1 by controlling the power supply to change the power of the circulating pump 1.

[0094] In an optional embodiment, the multi-channel thermometer is a JK808 multi-channel thermometer, and the eight temperature measuring points of the JK808 multi-channel thermometer are arranged at preset intervals on the pipes of the micro liquid cooling circuit system for temperature measurement; the multi-point data acquisition instrument is a 34970A multi-point data acquisition instrument; and the control power supply is a DC 0-5V power supply; so as to realize the heat dissipation test of the micro liquid cooling circuit system under different power conditions of the circulating pump 1.

[0095] In this embodiment, a multi-channel temperature measuring instrument and a multi-point data acquisition instrument are used to test the heat dissipation performance and working status of the micro liquid cooling circuit system, ensuring the reliability of the micro liquid cooling circuit system in actual use.

[0096] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A miniature liquid cooling circuit system, characterized in that, It includes a circulating pump (1), a preheater (2), an evaporator assembly (3), and a condenser (4), wherein: The outlet end of the circulating pump (1) and the inlet end of the preheater (2) are connected by a pipe. The outlet end of the preheater (2) and the inlet end of the evaporator assembly (3) are connected by a pipe. The outlet end of the evaporator assembly (3) and the inlet end of the condenser (4) are connected by a pipe. The inlet end of the circulating pump (1) and the outlet end of the condenser (4) are connected by a pipe to form a liquid cooling circuit. The evaporator assembly (3) is used for coupling with the circuit board. The circulating pump (1) is used to provide power to the working fluid in the liquid cooling circuit, and the preheater (2) is used to heat the liquid working fluid to a saturated state, wherein the saturated working fluid flows into the evaporator assembly (3). The evaporator assembly (3) is used to absorb the heat generated when the board is working in order to control the temperature of the board; the condenser (4) is used to cool the working fluid flowing out from the evaporator assembly (3) to form a liquid working fluid, which then re-enters the circulation pump (1). The evaporator assembly (3) is coupled to the board using a microchannel cold plate or a loop heat pipe (32). The loop heat pipe (32) includes a flat tube (321), a shell (322), and a vapor chamber (323), wherein: The flat tube (321) is a heat pipe formed by pressing the heat pipe body before entering the evaporator, so as to increase the contact surface between the evaporator assembly (3) and the plate. A shell (322) is welded on the top of the flat tube (321). The shell (322) only wraps around the top of the flat tube (321). The cavity formed between the shell (322) and the flat tube (321) is the steam chamber (323). The tube wall of the flat tube (321) wrapped by the shell (322) is provided with capillary pores (324). The capillary pores (324) are distributed along the length direction of the flat tube (321), and multiple capillary pores (324) are distributed in multiple rows. The capillary pores (324) are used to connect the steam chamber (323) and the flat tube (321) so that the gaseous working fluid enters the steam chamber (323) from the flat tube (321). The flat tube (321) is used to provide a flow channel for the liquid working fluid. Under the influence of the pore diameter (324), the length of the capillary pore (324), and the steam pressure in the steam chamber (323), the liquid working fluid can only overflow through the capillary pore (324) to a preset height in the steam chamber (323), so that the liquid working fluid fills the flat tube (321). The gaseous working fluid in the steam chamber (323) flows out of the steam chamber (323) from the capillary pore (324) at the front end of the steam chamber (323) along the flow direction of the working fluid in the whole system.

2. The micro liquid cooling circuit system according to claim 1, characterized in that, The micro liquid cooling circuit system further includes a regenerator (5), which includes a first port, a second port, a third port, and a fourth port. The first port and the second port form a flow channel, and the third port and the fourth port form a flow channel, wherein: The first port is connected to the outlet end of the circulating pump (1), the second port is connected to the inlet end of the preheater (2), the third port is connected to the outlet end of the evaporator assembly (3), and the fourth port is connected to the inlet end of the condenser (4). The regenerator (5) is used to heat the liquid working fluid from the circulating pump (1) using the saturated working fluid from the evaporator assembly (3).

3. The micro liquid cooling circuit system according to claim 1, characterized in that, The micro liquid cooling circuit system also includes a liquid reservoir (6), which is installed on the pipeline between the condenser (4) and the circulating pump (1) and is suitable for providing or storing working fluid during the operation of the micro liquid cooling circuit system.

4. The micro liquid cooling circuit system according to claim 3, characterized in that, The reservoir (6) is equipped with a heater, which is suitable for controlling the saturation pressure and saturation temperature of the working fluid in the reservoir (6), thereby realizing the saturation temperature control of the working fluid in the evaporator assembly (3).

5. The micro liquid cooling circuit system according to claim 1, characterized in that, The micro liquid cooling circuit system also includes a filter (7), which is installed on the pipeline between the condenser (4) and the circulating pump (1) and is suitable for filtering the working fluid.

6. The micro liquid cooling circuit system according to claim 1, characterized in that, The evaporator assembly (3) includes multiple evaporator units (31), and each evaporator unit (31) is provided with a disconnector (33) at both its outlet and inlet ends. The disconnector (33) is suitable for controlling the flow of the working fluid into and out of the evaporator, thereby realizing the flow control of the working fluid between the evaporators.

7. The micro liquid-cooled circuit system according to any one of claims 1 to 6, characterized in that, The micro liquid cooling circuit system also includes multiple pressure sensors (8), wherein: A pressure sensor (8) is installed on the pipe between the circulating pump (1) and the preheater (2), a pressure sensor (8) is installed on the pipe between the evaporator assembly (3) and the condenser (4), and a pressure sensor (8) is installed on the pipe between the condenser (4) and the circulating pump (1). The pressure sensor (8) is suitable for monitoring the pressure of pipes at various points in the micro liquid cooling circuit system.

8. A control method for a micro liquid-cooled circuit system, characterized in that, The control method is applied to the micro liquid cooling circuit system according to any one of claims 1 to 7, and the control method includes: The working state of the circulating pump (1) is controlled by the PLC control loop. The power of the circulating pump (1) is controlled according to the temperature of the card plate. The flow rate and pressure of the working fluid entering the preheater (2) are controlled to change the subcooling of the system. By controlling the saturation pressure and saturation temperature of the working fluid in the reservoir (6), the saturation temperature and saturation pressure of the working fluid in the evaporator assembly (3) can be controlled. By controlling the on / off state of each heat dissipation channel of the evaporator assembly (3), the flow rate of the working fluid between each heat dissipation channel is controlled, thereby achieving precise temperature control of the board.

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