Two-phase cold plate liquid cooling system and control method

Abstract

The present application provides a two-phase cold plate liquid cooling system and a control method. According to the present application, for parts which are cooled in series by the two-phase cold plate liquid cooling system, after a first evaporator cools a previous part, on the basis of the heat transfer requirements of a part cooled by a second evaporator, the quality of a refrigerant output from the first evaporator is adjusted to prevent the quality of the refrigerant from being too low or too high, and thus the refrigerant entering the second evaporator has proper quality, namely, the refrigerant entering the second evaporator has proper boiling point and heat exchange capacity, so that corresponding parts can be cooled to proper temperature, and large temperature difference between upstream and downstream parts is avoided. The solution solves the problem of the temperature of downstream parts in the series being lower than the temperature of upstream parts in the series, improves the temperature uniformity of multiple parts cooled in series, and then solves the problems of pressure oscillation, circulation stagnation and circulation reverse flow in the system, greatly improving the temperature uniformity of heat sources connected in series and the reliability of a series-parallel system.

Description

Two-phase cold plate liquid cooling system and control method

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application number 202410376231.6, filed with the Patent Office of China on March 29, 2024, entitled “Two-phase cold plate liquid cooling system and control method,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the technical field of computer equipment cooling, and in particular to a two-phase cold plate liquid cooling system and a control method thereof. Background Art

[0004] To meet the ever-increasing demand for computing power, the power density of a single cabinet is increasing. Within the next five years, 60kW cabinets will become mainstream. However, when the power density of a single cabinet reaches 20kW, air cooling systems will reach their cost-effective cooling limit.

[0005] Against this backdrop, liquid-cooled data center cooling technology with low PUE (Power Usage Effectiveness) and high thermal density has emerged. Two-phase cold plate liquid cooling utilizes the latent heat of the working fluid's vaporization phase change to quickly remove heat, undoubtedly offering high cooling efficiency. Furthermore, the latent heat of phase change is much greater than the sensible heat, resulting in a smaller circulating working fluid flow rate and lower power consumption in the circulating pump, which inevitably results in a lower PUE value. A two-phase cold plate liquid cooling system utilizes the boiling heat absorption and condensation heat release processes of the working fluid during its circulation process to collect and transport heat. Driven by a circulating pump, the working fluid flows into the evaporator. After entering the evaporator, the working fluid absorbs heat and transforms from a single-phase liquid to a gas-liquid two-phase state. After releasing heat through the condenser, the two-phase fluid transforms back to a liquid state and then enters the circulating pump, completing a complete cycle of heat absorption, transport, and release.

[0006] However, the pressure of the two-phase flow system is unstable, and the pump inlet requires a subcooling degree of 3 to 5°C. If it is too low, vaporization is likely to occur, affecting the life and reliability of the pump, and the heat dissipation efficiency drops sharply, especially when multiple heating components are connected in series. The heat exchange capacity of the front part of the refrigerant flow is weak due to the subcooling, and the convection heat transfer coefficient is one to two orders of magnitude lower than the phase change boiling heat transfer coefficient. After the mid-range part enters the two-phase heat exchange, the boiling point gradually decreases with the decrease in pressure, resulting in the temperature of the components in the rear part of the series being lower than the front part of the series. At the same time, due to the low pressure in the rear part, the two-phase flow ratio volume increases sharply, and the internal pressure of the system is prone to oscillation, which leads to circulation stagnation and, in severe cases, induces problems such as circulation backflow. Summary of the Invention

[0007] The present application provides a two-phase cold plate liquid cooling system and control method to solve the problem in the related art that when two-phase cold plate liquid cooling is used in series to cool multiple components, the temperature of the components in the later part of the series is lower than the temperature of the components in the earlier part of the series. It can also solve the problems of internal pressure oscillation, circulation stagnation and circulation backflow in the system caused by this.

[0008] In order to solve the above problems, according to the first aspect of the present application, the present application provides a two-phase cold plate liquid cooling system, including a condenser and a cooling branch, the cooling branch including a cooling pipe and a first evaporator, a gas-liquid rectifier and a second evaporator connected in series on the cooling pipe along the flow direction of the refrigerant, the outlet of the condenser, the cooling pipe and the inlet of the condenser are connected in sequence; the first evaporator and the second evaporator are used to cool different components respectively; wherein the gas-liquid rectifier adjusts the dryness of the refrigerant to enter the second evaporator according to the heat transfer requirements of the components cooled by the second evaporator.

[0009] In one embodiment, a dryness meter is provided between the first evaporator and the second evaporator, and the dryness meter is used to detect the dryness of the refrigerant before entering the second evaporator. The gas-liquid rectifier adjusts the dryness of the refrigerant to enter the second evaporator according to the detection result of the dryness meter.

[0010] In one embodiment, the heat transfer requirement of the components cooled by the second evaporator is obtained based on the second evaporator's own power consumption, the mass flow rate of the refrigerant in the second evaporator, and the latent heat of vaporization of the refrigerant. The expected dryness of the second evaporator to meet the heat transfer requirement of the components it cools is X. When the detection result of the dryness meter is lower than the expected dryness, the gas-liquid rectifier increases the dryness of the refrigerant therein through adjustment. When the detection result of the dryness meter is higher than the expected dryness, the gas-liquid rectifier reduces the dryness of the refrigerant therein through adjustment.

[0011] In one embodiment, X=A*Q^b*V^c*H^d; wherein Q is the power consumption of the components cooled by the second evaporator, in W; V is the mass flow rate of the refrigerant in the second evaporator, in M / S; H is the latent heat of vaporization of the refrigerant, in KJ / KG; b, c, and d are exponents, and A is a correction coefficient; the range of b is 0.3 to 0.6, the range of c is 0.1 to 0.36, and the range of d is 0.01 to 0.1.

[0012] In one embodiment, the two-phase cold plate liquid cooling system also includes a liquid reservoir, the gas-liquid rectifier includes a rectifier box, the rectifier box has a liquid replenishing port and an air replenishing port, the liquid replenishing port is connected to the liquid reservoir through a pipeline to replenish liquid refrigerant into the rectifier box, and the air replenishing port is connected to the condenser through a pipeline to replenish gaseous refrigerant into the rectifier box.

[0013] In one embodiment, the gas-liquid rectifier also includes a nozzle, which is located in the rectifier box and connected to the liquid infusion port. The liquid infusion port is connected to the liquid reservoir through a liquid infusion pipeline. A first liquid pump is provided on the liquid infusion pipeline. The gas infusion port is connected to the condenser through an gas infusion pipeline. A first air pump is provided on the gas infusion pipeline.

[0014] In one embodiment, the rectifier box has a two-phase gas-liquid inlet and a two-phase gas-liquid outlet, the two-phase gas-liquid inlet is connected to the outlet of the first evaporator, and the two-phase gas-liquid outlet is connected to the inlet of the second evaporator; the gas-liquid rectifier also includes a gas-liquid mixer arranged in the rectifier box, and the gas-liquid mixer is used to mix the refrigerant that will enter the two-phase gas-liquid outlet.

[0015] Alternatively, the two-phase cold plate liquid cooling system also includes a liquid reservoir, the gas-liquid rectifier includes a rectifier box, the rectifier box has a liquid filling port and a liquid discharge port, the liquid filling port is connected to the liquid reservoir through a pipeline to replenish liquid refrigerant into the rectifier box, and the liquid discharge port is connected to the liquid reservoir through a pipeline to discharge part of the liquid refrigerant in the rectifier box.

[0016] In one embodiment, the gas-liquid rectifier also includes a nozzle, which is located in the rectifier box and connected to the liquid infusion port, the liquid infusion port is connected to the liquid reservoir through a liquid infusion pipeline, a first liquid pump is provided on the liquid infusion pipeline, the liquid discharge port is connected to the liquid reservoir through a liquid discharge pipeline, and a second liquid pump is provided on the liquid discharge pipeline; or, the liquid infusion port and the liquid discharge port are the same port, and are connected to the liquid reservoir through a two-way pipeline, a two-way liquid pump is provided on the two-way pipeline, the two-way liquid pump can change the flow direction of the liquid refrigerant, or a reversing valve and a one-way liquid pump are provided on the two-way pipeline, and the reversing valve can change the flow direction of the liquid refrigerant.

[0017] In one embodiment, the rectifier box has a two-phase gas-liquid inlet and a two-phase gas-liquid outlet, the two-phase gas-liquid inlet is connected to the outlet of the first evaporator, and the two-phase gas-liquid outlet is connected to the inlet of the second evaporator; the gas-liquid rectifier also includes a gas-liquid separator and a gas-liquid mixer arranged in the rectifier box, the gas-liquid separator separates the refrigerant input from the two-phase gas-liquid inlet into gas and liquid, and the gas-liquid separator can be selectively operated or not operated, and the gas-liquid mixer is used to mix the refrigerant that will enter the two-phase gas-liquid outlet into gas and liquid.

[0018] Alternatively, the two-phase cold plate liquid cooling system also includes a liquid reservoir, the gas-liquid rectifier includes a rectifier box, the rectifier box has an exhaust port and an air supply port, the exhaust port is connected to the condenser through a pipeline to discharge part of the gaseous refrigerant in the rectifier box, and the air supply port is connected to the condenser through a pipeline to replenish the gaseous refrigerant into the rectifier box.

[0019] In one embodiment, the air supply port is connected to the condenser through an air supply pipeline, and a first air pump is provided on the air supply pipeline. The exhaust port is connected to the condenser through an exhaust pipeline, and a second air pump is provided on the exhaust pipeline; or, the air supply port and the exhaust port are the same port and are connected to the condenser through a two-way pipeline, and a two-way air pump is provided on the two-way pipeline, and the two-way air pump can change the flow direction of the gaseous refrigerant, or a reversing valve and a one-way air pump are provided on the two-way pipeline, and the reversing valve can change the flow direction of the gaseous refrigerant.

[0020] In one embodiment, the rectifier box has a two-phase gas-liquid inlet and a two-phase gas-liquid outlet, the two-phase gas-liquid inlet is connected to the outlet of the first evaporator, and the two-phase gas-liquid outlet is connected to the inlet of the second evaporator; the gas-liquid rectifier also includes a gas-liquid separator and a gas-liquid mixer arranged in the rectifier box, the gas-liquid separator separates the refrigerant input from the two-phase gas-liquid inlet into gas and liquid, and the gas-liquid separator can be selectively operated or not operated, and the gas-liquid mixer is used to mix the refrigerant that will enter the two-phase gas-liquid outlet into gas and liquid.

[0021] In one embodiment, the two-phase cold plate liquid cooling system also includes a liquid reservoir, the gas-liquid rectifier includes a rectifier box and a gas-liquid separator, the rectifier box is connected to the liquid reservoir and / or the condenser, the rectifier box has a two-phase gas-liquid inlet, the two-phase gas-liquid inlet is connected to the outlet of the first evaporator, the gas-liquid separator separates the refrigerant input from the two-phase gas-liquid inlet into gas and liquid, and the gas-liquid separator can selectively work or not work.

[0022] In one embodiment, the gas-liquid separator is movably arranged. When the gas-liquid separator moves toward the two-phase gas-liquid inlet, the gas-liquid separator works. When the gas-liquid separator moves to avoid the two-phase gas-liquid inlet, the gas-liquid separator does not work.

[0023] In one embodiment, the gas-liquid separator is a folded plate separator, which is swingably arranged. The folded plate separator switches its position by swinging to face or avoid the two-phase gas-liquid inlet.

[0024] In one embodiment, the two-phase cold plate liquid cooling system also includes a liquid reservoir, the gas-liquid rectifier includes a rectifying box and a gas-liquid mixer, the rectifying box is connected to the liquid reservoir and / or the condenser, the rectifying box has a two-phase gas-liquid outlet, the two-phase gas-liquid outlet is connected to the outlet of the second evaporator, and the gas-liquid mixer is used to mix the refrigerant that will enter the two-phase gas-liquid outlet.

[0025] In one embodiment, the gas-liquid mixer is oriented toward a two-phase gas-liquid outlet, and includes a plurality of wavy louvers arranged side by side, or the gas-liquid mixer includes a perforated plate, and the plurality of holes on the perforated plate are circular or polygonal.

[0026] In one embodiment, the two-phase cold plate liquid cooling system further includes a liquid reservoir, a circulation pump, a preheater and a plurality of regulating valves. The outlet of the condenser, the circulation pump, the preheater, the regulating valve and the inlet of the cooling pipe are connected in sequence. A regulating valve is provided on the pipeline between the gas-liquid rectifier and the liquid reservoir, and / or a regulating valve is provided on the pipeline between the gas-liquid rectifier and the condenser.

[0027] In one embodiment, there are multiple cooling branches, and the multiple cooling branches are arranged in parallel.

[0028] In one embodiment, the cooling branch also includes a front evaporator, which is connected to the cooling pipe and is located between the outlet of the condenser and the first evaporator. The front evaporator is used to cool low-power components, and the first evaporator and the second evaporator are respectively used to cool different high-power components.

[0029] In one embodiment, the two-phase cold plate liquid cooling system is used in at least one of the following computer devices:

[0030] In GPU servers, the front evaporator is used to cool the SW chip, and the first and second evaporators are used to cool the GPU.

[0031] For general servers, the front evaporator is used to cool the VR chip, and the first and second evaporators are used to cool the CPU.

[0032] Storage server, the front evaporator is used to cool the VR chip, and the first and second evaporators are used to cool the hard disk;

[0033] For switches, the front evaporator is used to cool the optical module components, and the first and second evaporators are used to cool the SW chips.

[0034] According to the second aspect of the present application, a control method is provided, which is used for the above-mentioned two-phase cold plate liquid cooling system. The control method includes: cooling different components respectively with the first evaporator and the second evaporator of the two-phase cold plate liquid cooling system; and performing at least one of the following adjustment operations on the gas-liquid rectifier located between the first evaporator and the second evaporator according to the heat transfer requirements of the components cooled by the second evaporator: replenishing liquid refrigerant, replenishing gaseous refrigerant, discharging part of the liquid refrigerant or discharging part of the gaseous refrigerant to adjust the dryness of the refrigerant to enter the second evaporator.

[0035] In one embodiment, the control method further includes: detecting the dryness E of the refrigerant output by the first evaporator, or detecting the dryness E of the refrigerant output by the gas-liquid rectifier; the heat transfer requirement of the component cooled by the second evaporator is obtained based on its own power consumption, the mass flow rate of the refrigerant in the second evaporator, and the latent heat of vaporization of the refrigerant; the expected dryness of the second evaporator to meet the heat transfer requirement of the component it cools is X, E is compared with X, and when E<X, the dryness of the refrigerant is increased through adjustment operation, and when E>X, the dryness of the refrigerant is reduced through adjustment operation.

[0036] In one embodiment, the adjustment operation is: when E<X, the gas-liquid rectifier is supplemented with gaseous refrigerant, and when E>X, the gas-liquid rectifier is supplemented with liquid refrigerant; or, when E<X, a portion of the liquid refrigerant in the gas-liquid rectifier is discharged, and when E>X, the gas-liquid rectifier is supplemented with liquid refrigerant; or, when E<X, the gas-liquid rectifier is supplemented with gaseous refrigerant, and when E>X, a portion of the gaseous refrigerant in the gas-liquid rectifier is discharged.

[0037] In one embodiment, X=A*Q^b*V^c*H^d; wherein, Q is the power consumption of the component cooled by the second evaporator, in W; V is the mass flow rate of the refrigerant, in M / S; H is the latent heat of vaporization of the refrigerant, in KJ / KG; b, c, and d are exponents, and A is a correction coefficient; B ranges from 0.3 to 0.6, c ranges from 0.1 to 0.36, and d ranges from 0.01 to 0.1.

[0038] In one embodiment, the gas-liquid rectifier includes a rectifier box and a gas-liquid separator located therein, the inlet of the rectifier box is connected to the first evaporator, and the control method further includes: when a part of the liquid refrigerant or a part of the gaseous refrigerant in the gas-liquid rectifier is discharged, the refrigerant input from the inlet of the rectifier box is separated into gas and liquid by the gas-liquid separator; when the liquid refrigerant or gaseous refrigerant in the gas-liquid rectifier is not discharged, the gas-liquid separator does not perform gas-liquid separation.

[0039] In one embodiment, a front evaporator is connected in series before the first evaporator, and the control method further includes: cooling low-power consumption components with the front evaporator, and cooling different high-power consumption components with the first evaporator and the second evaporator respectively.

[0040] In this solution, for components cooled in series via a two-phase cold plate liquid cooling system, after the first evaporator cools the preceding component, refrigerant flow is directed between the gas-liquid rectifier and the liquid reservoir and / or condenser based on the heat transfer requirements of the component cooled by the second evaporator. The dryness of the refrigerant output from the first evaporator can be adjusted to avoid excessively low or high dryness. This ensures that the refrigerant entering the second evaporator meets the heat transfer requirements of the components it cools. This ensures that the refrigerant entering the second evaporator has an appropriate boiling point and heat transfer capacity, allowing it to cool the corresponding component to an appropriate temperature and avoiding large temperature differences between the preceding and succeeding components. This solution utilizes the relationship between dryness and boiling heat transfer coefficient (the higher the dryness, the lower the boiling heat transfer coefficient) to control the dryness of the refrigerant entering the second evaporator, thereby controlling the temperature of the components cooled by the second evaporator. This solution solves the problem of components in the latter part of the series being colder than those in the preceding part, improves the temperature uniformity of multiple components cooled in series, and addresses issues such as internal pressure fluctuations, circulation stagnation, and circulation backflow within the system, significantly improving the temperature uniformity of the series heat source and the reliability of the series-parallel system. This creates technically feasible conditions for the large-scale application of two-phase cold plate liquid cooling technology in the data center field, opening the door to commercial applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings that constitute part of this application are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0042] FIG1 shows a schematic diagram of a two-phase cold plate liquid cooling system provided in Example 1 of the present application;

[0043] FIG2 shows a schematic diagram of the gas-liquid rectifier in FIG1 ;

[0044] FIG3 shows a schematic diagram of a two-phase cold plate liquid cooling system provided in Example 2 of the present application;

[0045] FIG4 shows a schematic diagram of the gas-liquid rectifier in FIG3 ;

[0046] FIG5 shows a schematic diagram of a two-phase cold plate liquid cooling system provided in Example 3 of the present application;

[0047] FIG6 shows a schematic diagram of the gas-liquid rectifier in FIG5 ;

[0048] FIG7 shows a schematic diagram of a two-phase cold plate liquid cooling system provided in Example 4 of the present application;

[0049] FIG8 shows a schematic diagram of a two-phase cold plate liquid cooling system provided in Example 5 of the present application.

[0050] Among them, the above-mentioned drawings include the following figure marks: 11. Condenser; 12. Liquid reservoir; 13. Circulation pump; 14. Preheater; 15. Regulating valve; 20. Cooling pipe; 31. First evaporator; 32. Second evaporator; 33. Front evaporator; 40. Gas-liquid rectifier; 41. Rectifier box; 42. Liquid replenishing port; 43. Gas replenishing port; 44. Nozzle; 45. Liquid drain port; 46. Exhaust port; 47. Gas-liquid separator; 48. Gas-liquid mixer; 50. Dryness meter; 61. First liquid pump; 62. Second liquid pump; 71. First air pump; 72. Second air pump. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0052] As shown in Figures 1 to 8, the present application provides a two-phase cold plate liquid cooling system, including a condenser 11 and a cooling branch, the cooling branch including a cooling pipe 20 and a first evaporator 31, a gas-liquid rectifier 40 and a second evaporator 32 connected in series on the cooling pipe 20 along the flow direction of the refrigerant, the outlet of the condenser 11, the cooling pipe 20, and the inlet of the condenser 11 are connected in sequence; the first evaporator 31 and the second evaporator 32 are used to cool different components respectively; wherein, the gas-liquid rectifier 40 adjusts the dryness of the refrigerant to enter the second evaporator 32 according to the heat transfer requirements of the components cooled by the second evaporator 32.

[0053] In this solution, for components cooled in series via a two-phase cold plate liquid cooling system, after the first evaporator 31 cools the preceding component, the gas-liquid rectifier 40 can adjust the dryness of the refrigerant entering the second evaporator 32 based on the heat transfer requirements of the component being cooled by the second evaporator 32, preventing the refrigerant from having too low or too high a dryness. This ensures that the refrigerant entering the second evaporator 32 has an appropriate dryness, meaning that the refrigerant entering the second evaporator 32 has an appropriate boiling point and heat exchange capacity, thereby cooling the corresponding component to an appropriate temperature and avoiding a large temperature difference between the front and rear components. Therefore, this solution solves the problem of the temperature of the components in the latter part of the series being lower than that in the former part, improves the temperature uniformity of multiple components cooled in series, and further resolves the problems of pressure oscillation, circulation stagnation, and circulation backflow within the system.

[0054] Dryness refers to the ratio of the mass of the gaseous fluid in a two-phase flow to the total mass of the two-phase flow, and its value ranges from 0 to 1. Specifically, the gas-liquid rectifier 40 adjusts the dryness by transferring refrigerant with other structures outside the gas-liquid rectifier 40, thereby changing the ratio of gaseous refrigerant to liquid refrigerant within the gas-liquid rectifier 40. Refrigerant transfer between the gas-liquid rectifier 40 and other structures can be performed by replenishing liquid refrigerant, replenishing gaseous refrigerant, discharging a portion of liquid refrigerant, or discharging a portion of gaseous refrigerant.

[0055] This solution uses the changing relationship between dryness and boiling heat transfer coefficient (the greater the dryness, the smaller the boiling heat transfer coefficient) to control the dryness of the refrigerant entering the second evaporator 32, thereby controlling the temperature of the components cooled by the second evaporator 32 to meet temperature requirements.

[0056] This two-phase cold plate liquid cooling system can be used for a variety of computer equipment, such as GPU (Graphics Processing Unit) servers, general servers, storage servers, switches, etc. The components cooled by the evaporator can be SW (Switch) chips, GPUs, CPUs (Central Processing Units), VR (Virtual Reality) chips, optical module components, and other components.

[0057] In this solution, a dryness meter 50 is installed between the first evaporator 31 and the second evaporator 32. The dryness meter 50 is used to detect the dryness of the refrigerant before it enters the second evaporator 32. The gas-liquid rectifier 40 adjusts the dryness of the refrigerant entering the second evaporator 32 based on the detection results of the dryness meter 50. The dryness meter 50 can be used to determine the dryness of the refrigerant before it enters the second evaporator 32, allowing adjustments to be made based on the detection results, facilitating operation.

[0058] For example, a dryness meter 50 is provided between the gas-liquid rectifier 40 and the first evaporator 31. The dryness meter 50 is used to detect the dryness of the refrigerant output from the first evaporator 31. The gas-liquid rectifier 40 adjusts the dryness of the refrigerant output from the first evaporator 31 based on the detection result of the dryness meter 50. Alternatively, a dryness meter 50 is provided between the gas-liquid rectifier 40 and the second evaporator 32. The dryness meter 50 is used to detect the dryness of the refrigerant output from the gas-liquid rectifier 40. The gas-liquid rectifier 40 adjusts the dryness of the refrigerant output from the first evaporator 31 based on the detection result of the dryness meter 50.

[0059] That is, this solution can detect the dryness of the refrigerant before entering the second evaporator 32, and adjust the refrigerant in the gas-liquid rectifier 40 based on the detection results, so that the control of the refrigerant dryness is more precise to meet the cooling requirements of the components cooled by the second evaporator 32, so that the temperature difference between the front and rear components on the series branch is reduced.

[0060] Of course, the dryness meter 50 may also be provided at other locations to monitor whether the dryness of the refrigerant at different locations meets the usage requirements.

[0061] In this solution, the heat transfer requirement of the component cooled by the second evaporator 32 is derived based on its own power consumption, the mass flow rate of the refrigerant in the second evaporator 32, and the latent heat of vaporization of the refrigerant. The heat transfer requirement of a component is the cooling capacity required for the component to maintain a normal operating temperature. This solution takes into account the component's own power consumption, the mass flow rate of the refrigerant in the second evaporator 32 of the liquid cooling system, and the latent heat of vaporization of the refrigerant. It also comprehensively considers the characteristics of the component itself and the characteristics of the liquid cooling system. The resulting dryness of the refrigerant, i.e., the heat exchange capacity of the refrigerant, can be more accurately matched to the component, ensuring that the component has a suitable operating temperature, avoiding the problem of excessive temperature difference between the downstream and upstream components of series cooling, and ensuring the temperature uniformity of the system.

[0062] Specifically, the expected dryness of the second evaporator 32 to meet the heat transfer requirements of the components it cools is X. If the dryness meter 50 test result is lower than the expected dryness, the gas-liquid rectifier 40 adjusts to increase the dryness of the refrigerant within it. If the dryness meter 50 test result is higher than the expected dryness, the gas-liquid rectifier 40 adjusts to reduce the dryness of the refrigerant within it. This ensures that the dryness of the refrigerant entering the second evaporator 32 reaches the expected dryness, improving temperature uniformity across multiple components cooled in series. The expected dryness is a range value.

[0063] Furthermore, X=A*Q^b*V^c*H^d; wherein, Q is the power consumption of the components cooled by the second evaporator 32, in W; V is the mass flow rate of the refrigerant, in M / S; H is the latent heat of vaporization of the refrigerant, in KJ / KG; b, c, and d are indexes, and A is a correction coefficient; the range of b is 0.3 to 0.6, the range of c is 0.1 to 0.36, and the range of d is 0.01 to 0.1.

[0064] This formula combines the characteristics of the component itself and the characteristics of the liquid cooling system, and is provided with a correction coefficient adjusted according to specific circumstances. Taking all factors into consideration, the calculated dryness is more in line with actual needs, so that the heat exchange capacity of the refrigerant entering the second evaporator 32 is more accurately matched with the heat transfer requirements of the component.

[0065] Among them, the power consumption Q of the components cooled by the second evaporator 32 has a greater impact on the required dryness, so the range of its corresponding index b is larger, so Q accounts for a larger proportion in the formula, which is more in line with the actual situation; the latent heat of vaporization V of the refrigerant has a relatively small impact on the cooling capacity of the liquid cooling system, so the range of its corresponding index d is larger, so V accounts for a larger proportion in the formula, which is more in line with the actual situation.

[0066] The above formula can be used to obtain the dryness required by the second evaporator 32 when cooling components, thereby enabling more accurate judgment and adjustment of the ratio of liquid to gas in the refrigerant within the gas-liquid rectifier 40 to achieve the desired dryness.

[0067] In some embodiments, the two-phase cold plate liquid cooling system further includes a liquid reservoir 12, which stores liquid refrigerant. The liquid reservoir 12 can be connected to the condenser 11 and supplied with liquid refrigerant through the condenser 11. The liquid reservoir 12 is used to supply liquid refrigerant to the gas-liquid rectifier 40 or to store some of the liquid refrigerant discharged from the gas-liquid rectifier 40 to adjust the refrigerant dryness.

[0068] In some embodiments, the condenser 11 can supply gaseous refrigerant to the gas-liquid rectifier 40 or store part of the gaseous refrigerant discharged from the gas-liquid rectifier 40 to adjust the refrigerant dryness.

[0069] In some embodiments, the gas-liquid rectifier 40 may also be connected to other external structures to transport gaseous refrigerant or liquid refrigerant, thereby adjusting the refrigerant dryness.

[0070] As shown in Figures 1 and 2, in the first embodiment, the gas-liquid rectifier 40 includes a rectifier box 41 having a liquid replenishment port 42 and a gas replenishment port 43. The liquid replenishment port 42 is connected to the liquid reservoir 12 via a pipeline to replenish liquid refrigerant into the rectifier box 41, and the gas replenishment port 43 is connected to the condenser 11 via a pipeline to replenish gaseous refrigerant into the rectifier box 41. In this way, if the dryness of the refrigerant output by the first evaporator 31 is higher than expected, liquid refrigerant can be replenished into the liquid replenishment port 42 via the liquid reservoir 12, thereby reducing the dryness of the two-phase refrigerant; if the dryness of the refrigerant output by the first evaporator 31 is lower than expected, gaseous refrigerant can be replenished into the gas replenishment port 43 via the condenser 11, thereby increasing the dryness of the two-phase refrigerant.

[0071] In other embodiments not shown in the figure, if necessary, a new evaporator can be connected in series after the second evaporator 32, and the new components can be cooled. A gas-liquid rectifier 40 is set between the second evaporator 32 and the subsequent evaporator. The dryness of the refrigerant before entering the next evaporator is adjusted by the gas-liquid rectifier 40 to ensure the cooling uniformity of the series system.

[0072] Specifically, the gas-liquid rectifier 40 also includes a nozzle 44, which is located in the rectifier box 41 and connected to the liquid infusion port 42. This allows the liquid refrigerant entering the rectifier box 41 to be distributed more evenly, which is conducive to gas-liquid mixing. The liquid infusion port 42 is connected to the liquid reservoir 12 through a liquid infusion pipeline, and a first liquid pump 61 is provided on the liquid infusion pipeline. The gas infusion port 43 is connected to the condenser 11 through an air infusion pipeline, and a first air pump 71 is provided on the air infusion pipeline. The first liquid pump 61 provides power for the flow of liquid refrigerant, and the first air pump 71 provides power for the flow of gaseous refrigerant. Among them, a regulating valve 15 can be provided on the liquid infusion pipeline and the air infusion pipeline, and the regulating valve 15 is used to adjust the flow or control the opening and closing of the pipeline.

[0073] Furthermore, as shown in FIG2 , the rectifier box 41 has a two-phase gas-liquid inlet and a two-phase gas-liquid outlet. The two-phase gas-liquid inlet is connected to the outlet of the first evaporator 31, and the two-phase gas-liquid outlet is connected to the inlet of the second evaporator 32. The gas-liquid rectifier 40 also includes a gas-liquid mixer 48 disposed within the rectifier box 41. The gas-liquid mixer 48 is used to mix the refrigerant entering the two-phase gas-liquid outlet. The gas-liquid mixer 48 can fully mix the refrigerant entering the second evaporator 32. The purpose is to ensure that the gas-liquid two-phase flow at the outlet is evenly mixed and then enters the next component to evenly absorb heat, thereby avoiding the rapid expansion of bubbles in the second evaporator 32 in the later stage, causing unstable flow and pressure fluctuations.

[0074] As shown in Figures 3 and 4, in the second embodiment, the gas-liquid rectifier 40 includes a rectifier box 41, which has a liquid replenishment port 42 and a liquid discharge port 45. The liquid replenishment port 42 is connected to the liquid reservoir 12 via a pipeline to replenish liquid refrigerant into the rectifier box 41, and the liquid discharge port 45 is connected to the liquid reservoir 12 via a pipeline to discharge a portion of the liquid refrigerant in the rectifier box 41. In this way, if the dryness of the refrigerant output by the first evaporator 31 is higher than expected, liquid refrigerant can be replenished into the liquid replenishment port 42 via the liquid reservoir 12, thereby reducing the dryness of the two-phase refrigerant; if the dryness of the refrigerant output by the first evaporator 31 is lower than expected, a portion of the liquid refrigerant can be discharged to the condenser 11 via the liquid discharge port 45, thereby increasing the dryness of the two-phase refrigerant.

[0075] The drain port 45 is located at the bottom of the rectifier box 41 so that the liquid refrigerant can be discharged smoothly. As shown in FIG4 , the bottom of the rectifier box 41 also has a drain port for discharging the refrigerant during maintenance.

[0076] Specifically, the gas-liquid rectifier 40 also includes a nozzle 44, which is located in the rectifier box 41 and connected to the liquid inlet 42. The liquid inlet 42 is connected to the liquid reservoir 12 via a liquid inlet pipeline. A first liquid pump 61 is provided on the liquid inlet pipeline. The liquid discharge port 45 is connected to the liquid reservoir 12 via a liquid discharge pipeline. A second liquid pump 62 is provided on the liquid discharge pipeline. In this way, the first liquid pump 61 and the second liquid pump 62 can provide power for the flow of liquid refrigerant. Among them, regulating valves 15 can be installed on the liquid inlet pipeline and the liquid discharge pipeline to adjust the flow or control the opening and closing of the pipeline.

[0077] Alternatively, in another embodiment (not shown), the liquid replenishment port 42 and the liquid discharge port 45 are the same port and are connected to the liquid reservoir 12 via a bidirectional pipeline. The bidirectional pipeline is provided with a bidirectional liquid pump that can change the flow direction of the liquid refrigerant, or the bidirectional pipeline is provided with a reversing valve and a one-way liquid pump that can change the flow direction of the liquid refrigerant. In this way, bidirectional flow of the refrigerant can be achieved without using two liquid pumps, thereby reducing costs.

[0078] Furthermore, as shown in FIG4 , the rectifying box 41 has a two-phase gas-liquid inlet and a two-phase gas-liquid outlet, the two-phase gas-liquid inlet is connected to the outlet of the first evaporator 31, and the two-phase gas-liquid outlet is connected to the inlet of the second evaporator 32; the gas-liquid rectifier 40 also includes a gas-liquid separator 47 and a gas-liquid mixer 48 arranged in the rectifying box 41, the gas-liquid separator 47 performs gas-liquid separation on the refrigerant input from the two-phase gas-liquid inlet, and the gas-liquid separator 47 can selectively work or not work, and the gas-liquid mixer 48 is used to mix the refrigerant that will enter the two-phase gas-liquid outlet.

[0079] Among them, the refrigerant entering the second evaporator 32 can be fully mixed with gas and liquid through the gas-liquid mixer 48. The purpose is to allow the gas-liquid two-phase flow at the outlet to mix evenly and then enter the next component to evenly absorb heat, so as to avoid the rapid expansion of bubbles in the second evaporator 32 in the later stage, causing unstable flow and pressure fluctuations. When it is necessary to increase the dryness and discharge the liquid refrigerant, the refrigerant entering the rectification box 41 can be separated into gas and liquid by the gas-liquid separator 47 first, so that the liquid refrigerant can be concentrated at the bottom of the rectification box 41, which is conducive to the extraction of part of the liquid refrigerant. When it is not necessary to discharge the liquid refrigerant to adjust the dryness, the gas-liquid separator 47 does not work, that is, no gas-liquid separation is performed.

[0080] As shown in Figures 5 and 6, in the third embodiment, the gas-liquid rectifier 40 includes a rectifier box 41, which has an exhaust port 46 and an air supply port 43. The exhaust port 46 is connected to the condenser 11 through a pipeline to discharge a portion of the gaseous refrigerant in the rectifier box 41, and the air supply port 43 is connected to the condenser 11 through a pipeline to replenish the gaseous refrigerant in the rectifier box 41. In this way, if the dryness of the refrigerant output by the first evaporator 31 is higher than expected, a portion of the gaseous refrigerant can be discharged to the condenser 11 through the exhaust port 46, thereby reducing the dryness of the two-phase refrigerant; if the dryness of the refrigerant output by the first evaporator 31 is lower than expected, gaseous refrigerant can be replenished to the air supply port 43 through the condenser 11, thereby increasing the dryness of the two-phase refrigerant. The exhaust port 46 is located at the top of the rectifier box 41 to facilitate the discharge of the gaseous refrigerant.

[0081] Specifically, the air supply port 43 is connected to the condenser 11 through an air supply pipeline, and a first air pump 71 is provided on the air supply pipeline. The exhaust port 46 is connected to the condenser 11 through an exhaust pipeline, and a second air pump 72 is provided on the exhaust pipeline; the first air pump 71 and the second air pump 72 provide power for the flow of gaseous refrigerant in different directions respectively.

[0082] Alternatively, in other embodiments not shown, the air supply port 43 and the air exhaust port 46 are the same port and are connected to the condenser 11 via a bidirectional pipeline. The bidirectional pipeline is provided with a bidirectional air pump that can change the flow direction of the gaseous refrigerant, or the bidirectional pipeline is provided with a reversing valve and a one-way air pump that can change the flow direction of the gaseous refrigerant. This can reduce the number of air pumps and reduce costs.

[0083] Furthermore, as shown in FIG6 , the rectifying box 41 has a two-phase gas-liquid inlet and a two-phase gas-liquid outlet, the two-phase gas-liquid inlet is connected to the outlet of the first evaporator 31, and the two-phase gas-liquid outlet is connected to the inlet of the second evaporator 32; the gas-liquid rectifier 40 also includes a gas-liquid separator 47 and a gas-liquid mixer 48 arranged in the rectifying box 41, the gas-liquid separator 47 performs gas-liquid separation on the refrigerant input from the two-phase gas-liquid inlet, and the gas-liquid separator 47 can selectively work or not work, and the gas-liquid mixer 48 is used to mix the refrigerant that will enter the two-phase gas-liquid outlet.

[0084] Among them, the refrigerant entering the second evaporator 32 can be fully mixed with gas and liquid through the gas-liquid mixer 48. The purpose is to allow the gas-liquid two-phase flow at the outlet to mix evenly and then enter the next component to evenly absorb heat, so as to avoid the rapid expansion of bubbles in the second evaporator 32 in the later stage, causing unstable flow and pressure fluctuations. When it is necessary to reduce the dryness and discharge the gaseous refrigerant, the refrigerant entering the rectification box 41 can be separated into gas and liquid by the gas-liquid separator 47 first, so that the gaseous refrigerant can be concentrated on the top of the rectification box 41, which is conducive to extracting a part of the gaseous refrigerant. When it is not necessary to discharge the gaseous refrigerant to adjust the dryness, the gas-liquid separator 47 does not work, that is, no gas-liquid separation is performed.

[0085] In some embodiments of the present invention, the gas-liquid rectifier 40 includes a rectifier box 41 and a gas-liquid separator 47. The rectifier box 41 is connected to the liquid reservoir 12 and / or the condenser 11. The rectifier box 41 has a two-phase gas-liquid inlet, which is connected to the outlet of the first evaporator 31. The gas-liquid separator 47 performs gas-liquid separation on the refrigerant input from the two-phase gas-liquid inlet. The gas-liquid separator 47 can be selectively operated or not. In this way, when it is necessary to discharge a portion of the liquid refrigerant or the gaseous refrigerant, the two-phase refrigerant entering the rectifier box 41 can be separated into gas and liquid, thereby making it easier to discharge the liquid refrigerant or the gaseous refrigerant and improving the efficiency of adjusting the dryness.

[0086] Specifically, the gas-liquid separator 47 is movably arranged. When the gas-liquid separator 47 is moved toward the two-phase gas-liquid inlet, the gas-liquid separator 47 is in operation. When the gas-liquid separator 47 is moved away from the two-phase gas-liquid inlet, the gas-liquid separator 47 is inoperative. In this way, the gas-liquid separator 47 can be switched to be inoperative or inoperative by moving the gas-liquid separator 47, which is convenient for operation.

[0087] For example, as shown in Figures 4 and 6, the gas-liquid separator 47 is a folding plate separator, which is swingably arranged. The folding plate separator switches its position by swinging to face or avoid the two-phase gas-liquid inlet. This method can achieve functional requirements with a simple structure.

[0088] In this solution, the gas-liquid rectifier 40 includes a rectifying box 41 and a gas-liquid mixer 48. The rectifying box 41 is connected to the liquid reservoir 12 and / or the condenser 11. The rectifying box 41 has a two-phase gas-liquid outlet, which is connected to the outlet of the second evaporator 32. The gas-liquid mixer 48 is used to mix the refrigerant that will enter the two-phase gas-liquid outlet.

[0089] Through the above-mentioned setting, the gas-liquid mixer 48 can fully mix the refrigerant entering the second evaporator 32, so that the gas-liquid two-phase flow at the outlet can be evenly mixed and enter the next component to evenly absorb heat, avoiding the rapid expansion of bubbles in the second evaporator 32 in the later stage, causing unstable flow and pressure fluctuations.

[0090] Specifically, the gas-liquid mixer 48 is oriented toward the two-phase gas-liquid outlet and includes a plurality of wavy louvers arranged side by side, or includes an orifice plate with a plurality of circular or polygonal holes. In other words, the gas-liquid mixer 48 can have various structures to achieve the desired gas-liquid mixing effect.

[0091] As shown in Figures 1, 3 and 5, in this solution, the two-phase cold plate liquid cooling system also includes a liquid reservoir 12, a circulating pump 13, a preheater 14 and multiple regulating valves 15. The outlet of the condenser 11, the circulating pump 13, the preheater 14, the regulating valve 15 and the inlet of the cooling pipe 20 are connected in sequence. The regulating valve 15 is provided on the pipeline between the gas-liquid rectifier 40 and the liquid reservoir 12, and / or the regulating valve 15 is provided on the pipeline between the gas-liquid rectifier 40 and the condenser 11.

[0092] The circulation pump 13 provides power for the flow of refrigerant in the entire system. The refrigerant passes through the preheater 14 from the circulation pump 13, reduces the subcooling degree through preheating, then enters the regulating valve 15 for throttling, and then enters the cooling pipe 20 of the cooling branch with appropriate flow rate and subcooling degree.

[0093] As shown in Figures 7 and 8, in a two-phase cold plate liquid cooling system, multiple cooling branches can be configured and connected in parallel. Different cooling branches cool different components, allowing multiple devices to share a single liquid cooling system, thus reducing costs. For example, Figure 7 shows two cooling branches running in parallel, while Figure 8 shows three cooling branches running in parallel.

[0094] Among them, multiple gas-liquid rectifiers 40 in different cooling branches in the two-phase cold plate liquid cooling system can share a liquid pump or an air pump, and the gas-liquid rectifier 40 and the liquid pump or the air pump are controlled to be on and off respectively through the branch pipelines and regulating valves 15 corresponding to the gas-liquid rectifier 40.

[0095] As shown in Figure 7, the two-phase cold plate liquid cooling system also includes a data acquisition module and a control module. The data acquisition module is electrically connected to different components, such as the evaporator, the regulating valve 15, the gas-liquid rectifier 40, and the dryness meter 50. Information is collected through the data acquisition module. In addition, the data acquisition module and different components are electrically connected to the control module, and the gas-liquid rectifier 40 and the like are controlled by the control module, thereby improving the degree of automation of the two-phase cold plate liquid cooling system.

[0096] In this solution, the cooling branch also includes a front evaporator 33, which is connected to the cooling pipe 20 and is located between the outlet of the condenser 11 and the first evaporator 31. The front evaporator 33 is used to cool low-power components, and the first evaporator 31 and the second evaporator 32 are respectively used to cool different high-power components.

[0097] Through the above-mentioned arrangement, the refrigerant with supercooling and weak heat exchange capacity output from the condenser 11 first passes through the front evaporator 33 to cool the low-power components, which not only meets the cooling needs of the low-power components, but also allows the refrigerant to become a saturated refrigerant after heat exchange, thereby improving the heat exchange capacity, and then enters the first evaporator 31 and the second evaporator 32 to cool the high-power components. In this way, the power consumption characteristics of multiple components connected in series by the cooling branches are used for cooling, which can better cool different components, meet the cooling needs of different components, and make full use of energy.

[0098] In this solution, the two-phase cold plate liquid cooling system can be used for at least one of the following computer devices:

[0099] In the GPU server, the front evaporator 33 is used to cool the SW chip, and the first evaporator 31 and the second evaporator 32 are used to cool the GPU;

[0100] For general servers, the front evaporator 33 is used to cool the VR chip, and the first evaporator 31 and the second evaporator 32 are used to cool the CPU;

[0101] In the storage server, the front evaporator 33 is used to cool the VR chip, and the first evaporator 31 and the second evaporator 32 are used to cool the hard disk;

[0102] In the switch, the front evaporator 33 is used to cool the optical module components, and the first evaporator 31 and the second evaporator 32 are used to cool the SW chip.

[0103] This two-phase cold plate liquid cooling system can be used to cool different computer equipment, with the evaporator placement tailored to the specific characteristics of the equipment. This solution creates technically feasible conditions for the large-scale application of two-phase cold plate liquid cooling technology in data centers.

[0104] The present application also provides a control method, which is used for the above-mentioned two-phase cold plate liquid cooling system. The control method includes: cooling different components respectively with the first evaporator 31 and the second evaporator 32 of the two-phase cold plate liquid cooling system; and performing at least one of the following adjustment operations on the gas-liquid rectifier 40 located between the first evaporator 31 and the second evaporator 32 according to the heat transfer requirements of the components cooled by the second evaporator 32: replenishing liquid refrigerant, replenishing gaseous refrigerant, discharging a portion of the liquid refrigerant, or discharging a portion of the gaseous refrigerant to adjust the dryness of the refrigerant output from the first evaporator 31.

[0105] In this solution, for components cooled in series by a two-phase cold plate liquid cooling system, after the first evaporator 31 cools the preceding component, the refrigerant is allowed to flow between the gas-liquid rectifier 40 and other structures, discharging or replenishing the liquid or gaseous refrigerant, depending on the heat transfer requirements of the component cooled by the second evaporator 32. This allows the dryness of the refrigerant output from the first evaporator 31 to be adjusted to avoid excessively low or high dryness. This ensures that the refrigerant entering the second evaporator 32 has an appropriate dryness, i.e., the refrigerant entering the second evaporator 32 has an appropriate boiling point and heat exchange capacity, thereby cooling the corresponding component to an appropriate temperature and avoiding a large temperature difference between the front and rear components. Therefore, this solution solves the problem of the temperature of the components in the latter part of the series being lower than the temperature of the components in the former part of the series, improves the temperature uniformity of the multiple components cooled in series, and further solves the problems of pressure oscillation, circulation stagnation, and circulation backflow within the system.

[0106] Furthermore, the control method also includes: detecting the dryness E of the refrigerant output by the first evaporator 31, or detecting the dryness E of the refrigerant output by the gas-liquid rectifier 40; the heat transfer requirement of the component cooled by the second evaporator 32 is obtained based on its own power consumption, the mass flow rate of the refrigerant in the second evaporator 32, and the latent heat of vaporization of the refrigerant; the expected dryness of the second evaporator 32 to meet the heat transfer requirement of the component it cools is X, and E is compared with X. When E<X, the dryness of the refrigerant is increased through adjustment operation, and when E>X, the dryness of the refrigerant is reduced through adjustment operation.

[0107] In this way, this solution can detect the dryness of the refrigerant before entering the second evaporator 32, and adjust the refrigerant in the gas-liquid rectifier 40 based on the detection results, so that the control of the refrigerant dryness is more precise to meet the cooling requirements of the components cooled by the second evaporator 32, so that the temperature difference between the front and rear components on the series branch is reduced.

[0108] In this method, the heat transfer requirement of the component cooled by the second evaporator 32 is derived based on its own power consumption, the mass flow rate of the refrigerant in the second evaporator 32, and the latent heat of vaporization of the refrigerant. The heat transfer requirement of a component is the cooling capacity required for the component to maintain a normal operating temperature. This solution takes into account the component's own power consumption, the mass flow rate of the refrigerant in the second evaporator 32 of the liquid cooling system, and the latent heat of vaporization of the refrigerant. It also comprehensively considers the characteristics of the component itself and the characteristics of the liquid cooling system. The dryness of the refrigerant obtained by such adjustment, that is, the heat exchange capacity of the refrigerant, can be more accurately matched with the component, ensuring that the component has a suitable operating temperature, avoiding the problem of excessive temperature difference between the downstream components and the upstream components of the series cooling, and ensuring the temperature uniformity of the system.

[0109] The adjustment operation can be performed in the following three different ways:

[0110] In the case of E<X, the gaseous refrigerant is added to the gas-liquid rectifier 40 , and in the case of E>X, the liquid refrigerant is added to the gas-liquid rectifier 40 ; or,

[0111] In the case of E<X, a portion of the liquid refrigerant in the gas-liquid rectifier 40 is discharged, and in the case of E>X, the liquid refrigerant is replenished to the gas-liquid rectifier 40; or,

[0112] When E<X, the gaseous refrigerant is added to the gas-liquid rectifier 40 , and when E>X, a portion of the gaseous refrigerant in the gas-liquid rectifier 40 is discharged.

[0113] The above three methods can all adjust the dryness of the refrigerant in the gas-liquid rectifier 40 , and the specific method to be adopted can be selected according to needs.

[0114] In this method, X=A*Q^b*V^c*H^d; wherein, Q is the power consumption of the components cooled by the second evaporator 32, in W; V is the mass flow rate of the refrigerant, in M / S; H is the latent heat of vaporization of the refrigerant, in KJ / KG; b, c, and d are indexes, and A is a correction coefficient; the range of B is 0.3 to 0.6, the range of c is 0.1 to 0.36, and the range of d is 0.01 to 0.1.

[0115] This formula combines the characteristics of the component itself and the characteristics of the liquid cooling system, and is provided with a correction coefficient adjusted according to specific circumstances. Taking all factors into consideration, the calculated dryness is more in line with actual needs, so that the heat exchange capacity of the refrigerant entering the second evaporator 32 is more accurately matched with the heat transfer requirements of the component.

[0116] Among them, the power consumption Q of the components cooled by the second evaporator 32 has a greater impact on the required dryness, so the range of its corresponding index b is larger, so Q accounts for a larger proportion in the formula, which is more in line with the actual situation; the latent heat of vaporization V of the refrigerant has a relatively small impact on the cooling capacity of the liquid cooling system, so the range of its corresponding index d is larger, so V accounts for a larger proportion in the formula, which is more in line with the actual situation.

[0117] The above formula can be used to obtain the dryness required by the second evaporator 32 when cooling components, thereby enabling more accurate judgment and adjustment of the ratio of liquid to gas in the refrigerant within the gas-liquid rectifier 40 to achieve the desired dryness.

[0118] In this method, the gas-liquid rectifier 40 includes a rectifying box 41 and a gas-liquid separator 47 located therein, and the inlet of the rectifying box 41 is connected to the first evaporator 31. The control method also includes: when a part of the liquid refrigerant or a part of the gaseous refrigerant in the gas-liquid rectifier 40 is discharged, the refrigerant input from the inlet of the rectifying box 41 is separated into gas and liquid by the gas-liquid separator 47; when the liquid refrigerant or gaseous refrigerant in the gas-liquid rectifier 40 is not discharged, the gas-liquid separator 47 does not perform gas-liquid separation.

[0119] By using this method, when it is necessary to increase the dryness and discharge the liquid refrigerant, or when it is necessary to reduce the dryness and discharge the gaseous refrigerant, the refrigerant entering the rectifying box 41 can be first separated into gas and liquid by the gas-liquid separator 47. In this way, the liquid refrigerant can be concentrated at the bottom of the rectifying box 41, and the gaseous refrigerant can be concentrated at the upper part of the rectifying box 41, which is conducive to extracting a portion of the liquid refrigerant or the gaseous refrigerant, thereby improving operating efficiency. When it is not necessary to discharge the liquid refrigerant or the gaseous refrigerant to adjust the dryness, the gas-liquid separator 47 does not work, that is, no gas-liquid separation is performed.

[0120] Furthermore, a front evaporator 33 is connected in series before the first evaporator 31 , and the control method further includes: cooling the low-power consumption components with the front evaporator 33 , and cooling different high-power consumption components with the first evaporator 31 and the second evaporator 32 respectively.

[0121] Through the above steps, the refrigerant with supercooling and weak heat exchange capacity output from the condenser 11 first passes through the front evaporator 33 to cool the low-power components, which not only meets the cooling needs of the low-power components, but also allows the refrigerant to become a saturated refrigerant after heat exchange, thereby improving the heat exchange capacity, and then enters the first evaporator 31 and the second evaporator 32 to cool the high-power components. In this way, the power consumption characteristics of multiple components connected in series by the cooling branches are used for cooling, which can better cool different components, meet the cooling needs of different components, and make full use of energy.

[0122] In the above solution, the characteristics of the node's internal heat source are fully utilized to solve the supercooling problem. Taking the GPU server as an example, the refrigerant with a certain degree of supercooling first enters the low-power, low-temperature-sensitivity SW chip through the front evaporator 33 to absorb heat and become saturated refrigerant before entering the GPU with higher temperature uniformity requirements to absorb heat. A dryness meter 50 is set when flowing through each level of GPU heat source. The changing relationship between dryness and boiling heat transfer coefficient (the greater the dryness, the smaller the boiling heat transfer coefficient) is used to control the temperature of the subsequent GPU. That is, the evaporator corresponding to the subsequent GPU has a lower pressure and a lower boiling point due to pressure drop, so the temperature of the subsequent GPU will also be lower than that of the previous GPU. The dryness of the evaporator corresponding to the subsequent GPU is controlled at the expected dryness value to compensate for the impact of the low boiling point. When the temperature of the previous and subsequent GPUs deviates, the dryness meter 50 is first used to detect and determine the adjustment direction. A gas-liquid rectifier 40 is set before the second evaporator 32 to adjust the refrigerant dryness function.

[0123] The technology provided in this application not only fundamentally solves the problem of lower component temperatures in the later stages of a series connection than in the earlier stages, but also addresses the resulting challenges of internal system pressure fluctuations, circulation stagnation, and backflow, significantly improving the temperature uniformity of the series heat source and the reliability of the series-parallel system. This creates technically feasible conditions for the large-scale application of two-phase cold plate liquid cooling technology in data centers, opening the door to commercial application.

[0124] The two-phase cold plate liquid cooling system and control method provided by this solution can be applied to general-purpose, high-performance, and AI servers. When these products use the liquid cooling technology of this solution, they will have at least the following beneficial effects:

[0125] 1. The lowest PUE can be as low as 1.1, which helps to achieve green energy saving;

[0126] 2. Using phase change cold plates and immersion liquid cooling to improve heat exchange efficiency can break through the heat dissipation bottleneck of high-power and high-heat flux density chips, high-density servers, and high-power density cabinets, meeting the product's heat dissipation needs for many years;

[0127] 3. Full coverage of liquid cooling, good temperature uniformity;

[0128] 4. The refrigerant uses insulating medium, which has higher reliability and safety than water cooling.

[0129] 5. Compared with immersion liquid cooling, the technology of this solution can significantly save the system immersion liquid cost while also improving the reliability of the system.

[0130] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

[0131] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0132] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to actual proportional relationships. The technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0133] In the description of this application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of this application; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0134] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0135] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

Claims

1. A two-phase cold plate liquid cooling system, characterized in that: The invention comprises a condenser (11) and a cooling branch, wherein the cooling branch comprises a cooling pipe (20) and a first evaporator (31), a gas-liquid rectifier (40) and a second evaporator (32) connected in series on the cooling pipe (20) along the flow direction of the refrigerant, wherein the outlet of the condenser (11), the cooling pipe (20) and the inlet of the condenser (11) are connected in sequence; the first evaporator (31) and the second evaporator (32) are respectively configured to cool different components; wherein the gas-liquid rectifier (40) adjusts the dryness of the refrigerant to be introduced into the second evaporator (32) according to the heat transfer requirements of the components cooled by the second evaporator (32).

2. The two-phase cold plate liquid cooling system according to claim 1, characterized in that: A dryness meter (50) is provided between the first evaporator (31) and the second evaporator (32). The dryness meter (50) is configured to detect the dryness of the refrigerant before entering the second evaporator (32). The gas-liquid rectifier (40) adjusts the dryness of the refrigerant to enter the second evaporator (32) according to the detection result of the dryness meter (50).

3. The two-phase cold plate liquid cooling system according to claim 2, characterized in that: The heat transfer requirement of the components cooled by the second evaporator (32) is obtained based on its own power consumption, the mass flow rate of the refrigerant in the second evaporator (32), and the latent heat of vaporization of the refrigerant. The expected dryness of the components cooled by the second evaporator (32) is X. When the detection result of the dryness meter (50) is lower than the expected dryness, the gas-liquid rectifier (40) increases the dryness of the refrigerant therein by adjustment. When the detection result of the dryness meter (50) is higher than the expected dryness, the gas-liquid rectifier (40) reduces the dryness of the refrigerant therein by adjustment.

4. The two-phase cold plate liquid cooling system according to claim 3, characterized in that: X=A*Q^b*V^c*H^d; Wherein, Q is the power consumption of the components cooled by the second evaporator (32), in W; V is the mass flow rate of the refrigerant in the second evaporator (32), in M / S; H is the latent heat of vaporization of the refrigerant, in KJ / KG; b, c, and d are indices, and A is a correction coefficient; the range of b is 0.3 to 0.6, the range of c is 0.1 to 0.36, and the range of d is 0.01 to 0.

1.

5. The two-phase cold plate liquid cooling system according to claim 1, characterized in that: The two-phase cold plate liquid cooling system further includes a liquid reservoir (12), the gas-liquid rectifier (40) includes a rectifier box (41), the rectifier box (41) has a liquid replenishing port (42) and an air replenishing port (43), the liquid replenishing port (42) is connected to the liquid reservoir (12) through a pipeline to replenish liquid refrigerant into the rectifier box (41), and the air replenishing port (43) is connected to the condenser (11) through a pipeline to replenish gaseous refrigerant into the rectifier box (41).

6. The two-phase cold plate liquid cooling system according to claim 5, characterized in that: The gas-liquid rectifier (40) further includes a nozzle (44), the nozzle (44) being located in the rectifier box (41) and connected to the liquid infusion port (42), the liquid infusion port (42) being connected to the liquid reservoir (12) via a liquid infusion pipeline, a first liquid pump (61) being provided on the liquid infusion pipeline, the gas infusion port (43) being connected to the condenser (11) via an gas infusion pipeline, a first gas pump (71) being provided on the gas infusion pipeline.

7. The two-phase cold plate liquid cooling system according to claim 5, characterized in that: The rectifying box (41) has a two-phase gas-liquid inlet and a two-phase gas-liquid outlet, the two-phase gas-liquid inlet is connected to the outlet of the first evaporator (31), and the two-phase gas-liquid outlet is connected to the inlet of the second evaporator (32); the gas-liquid rectifier (40) also includes a gas-liquid mixer (48) arranged in the rectifying box (41), and the gas-liquid mixer (48) is configured to mix the refrigerant entering the two-phase gas-liquid outlet with gas and liquid.

8. The two-phase cold plate liquid cooling system according to claim 1, characterized in that: The two-phase cold plate liquid cooling system also includes a liquid reservoir (12), the gas-liquid rectifier (40) includes a rectifier box (41), the rectifier box (41) has a liquid replenishing port (42) and a liquid drain port (45), the liquid replenishing port (42) is connected to the liquid reservoir (12) through a pipeline to replenish liquid refrigerant into the rectifier box (41), and the liquid drain port (45) is connected to the liquid reservoir (12) through a pipeline to discharge a portion of the liquid refrigerant in the rectifier box (41).

9. The two-phase cold plate liquid cooling system according to claim 8, characterized in that: The gas-liquid rectifier (40) further comprises a nozzle (44), the nozzle (44) being located in the rectifier box (41) and connected to the liquid infusion port (42), the liquid infusion port (42) being connected to the liquid reservoir (12) via a liquid infusion pipeline, a first liquid pump (61) being provided on the liquid infusion pipeline, the liquid discharge port (45) being connected to the liquid reservoir (12) via a liquid discharge pipeline, a second liquid pump (62) being provided on the liquid discharge pipeline; Alternatively, the liquid replenishing port (42) and the liquid discharging port (45) are the same port and are connected to the liquid reservoir (12) via a two-way pipeline, a two-way liquid pump is provided on the two-way pipeline, and the two-way liquid pump can change the flow direction of the liquid refrigerant, or a reversing valve and a one-way liquid pump are provided on the two-way pipeline, and the reversing valve can change the flow direction of the liquid refrigerant.

10. The two-phase cold plate liquid cooling system according to claim 8, characterized in that: The rectifier box (41) has a two-phase gas-liquid inlet and a two-phase gas-liquid outlet, the two-phase gas-liquid inlet is connected to the outlet of the first evaporator (31), and the two-phase gas-liquid outlet is connected to the inlet of the second evaporator (32); the gas-liquid rectifier (40) also includes a gas-liquid separator (47) and a gas-liquid mixer (48) arranged in the rectifier box (41), the gas-liquid separator (47) performs gas-liquid separation on the refrigerant input from the two-phase gas-liquid inlet, and the gas-liquid separator (47) can be selectively operated or not operated, and the gas-liquid mixer (48) is configured to perform gas-liquid mixing on the refrigerant that will enter the two-phase gas-liquid outlet.

11. The two-phase cold plate liquid cooling system according to claim 1, characterized in that: The two-phase cold plate liquid cooling system also includes a liquid reservoir (12), the gas-liquid rectifier (40) includes a rectifier box (41), the rectifier box (41) has an exhaust port (46) and an air supply port (43), the exhaust port (46) is connected to the condenser (11) through a pipeline to discharge a portion of the gaseous refrigerant in the rectifier box (41), and the air supply port (43) is connected to the condenser (11) through a pipeline to replenish the gaseous refrigerant in the rectifier box (41).

12. The two-phase cold plate liquid cooling system according to claim 11, characterized in that: The air supply port (43) is connected to the condenser (11) via an air supply pipeline, a first air pump (71) is provided on the air supply pipeline, and the exhaust port (46) is connected to the condenser (11) via an exhaust pipeline, a second air pump (72) is provided on the exhaust pipeline; Alternatively, the air supply port (43) and the air exhaust port (46) are the same port and are connected to the condenser (11) via a two-way pipeline, a two-way air pump is provided on the two-way pipeline, and the two-way air pump can change the flow direction of the gaseous refrigerant, or a reversing valve and a one-way air pump are provided on the two-way pipeline, and the reversing valve can change the flow direction of the gaseous refrigerant.

13. The two-phase cold plate liquid cooling system according to claim 11, characterized in that: The rectifier box (41) has a two-phase gas-liquid inlet and a two-phase gas-liquid outlet, the two-phase gas-liquid inlet is connected to the outlet of the first evaporator (31), and the two-phase gas-liquid outlet is connected to the inlet of the second evaporator (32); the gas-liquid rectifier (40) also includes a gas-liquid separator (47) and a gas-liquid mixer (48) arranged in the rectifier box (41), the gas-liquid separator (47) performs gas-liquid separation on the refrigerant input from the two-phase gas-liquid inlet, and the gas-liquid separator (47) can be selectively operated or not operated, and the gas-liquid mixer (48) is configured to perform gas-liquid mixing on the refrigerant that will enter the two-phase gas-liquid outlet.

14. The two-phase cold plate liquid cooling system according to claim 1, characterized in that: The two-phase cold plate liquid cooling system also includes a liquid reservoir (12), the gas-liquid rectifier (40) includes a rectifying box (41) and a gas-liquid separator (47), the rectifying box (41) is connected to the liquid reservoir (12) and / or the condenser (11), the rectifying box (41) has a two-phase gas-liquid inlet, the two-phase gas-liquid inlet is connected to the outlet of the first evaporator (31), the gas-liquid separator (47) performs gas-liquid separation on the refrigerant input from the two-phase gas-liquid inlet, and the gas-liquid separator (47) can be selectively operated or not operated.

15. The two-phase cold plate liquid cooling system according to claim 14, characterized in that: The gas-liquid separator (47) is movably arranged. When the gas-liquid separator (47) moves toward the two-phase gas-liquid inlet, the gas-liquid separator (47) works. When the gas-liquid separator (47) moves to avoid the two-phase gas-liquid inlet, the gas-liquid separator (47) does not work.

16. The two-phase cold plate liquid cooling system according to claim 15, characterized in that: The gas-liquid separator (47) is a folding plate separator, which is swingably arranged. The folding plate separator switches its position by swinging to face or avoid the two-phase gas-liquid inlet.

17. The two-phase cold plate liquid cooling system according to claim 1, characterized in that: The two-phase cold plate liquid cooling system also includes a liquid reservoir (12), the gas-liquid rectifier (40) includes a rectifying box (41) and a gas-liquid mixer (48), the rectifying box (41) is connected to the liquid reservoir (12) and / or the condenser (11), the rectifying box (41) has a two-phase gas-liquid outlet, the two-phase gas-liquid outlet is connected to the outlet of the second evaporator (32), and the gas-liquid mixer (48) is configured to perform gas-liquid mixing on the refrigerant that will enter the two-phase gas-liquid outlet.

18. The two-phase cold plate liquid cooling system according to claim 17, characterized in that: The gas-liquid mixer (48) faces the two-phase gas-liquid outlet, and the gas-liquid mixer (48) includes a plurality of wavy louvers arranged side by side, or the gas-liquid mixer (48) includes a perforated plate, and the plurality of holes on the perforated plate are circular or polygonal.

19. The two-phase cold plate liquid cooling system according to claim 1, characterized in that: The two-phase cold plate liquid cooling system further includes a liquid reservoir (12), a circulation pump (13), a preheater (14) and a plurality of regulating valves (15); the outlet of the condenser (11), the circulation pump (13), the preheater (14), the regulating valve (15) and the inlet of the cooling pipe (20) are connected in sequence; the regulating valve (15) is provided on the pipeline between the gas-liquid rectifier (40) and the liquid reservoir (12), and / or the regulating valve (15) is provided on the pipeline between the gas-liquid rectifier (40) and the condenser (11).

20. The two-phase cold plate liquid cooling system according to claim 1, characterized in that: There are multiple cooling branches, and the multiple cooling branches are arranged in parallel.

21. The two-phase cold plate liquid cooling system according to any one of claims 1 to 20, characterized in that: The cooling branch further includes a front evaporator (33), which is connected to the cooling pipe (20) and is located between the outlet of the condenser (11) and the first evaporator (31). The front evaporator (33) is configured to cool low-power components, and the first evaporator (31) and the second evaporator (32) are respectively configured to cool different high-power components.

22. The two-phase cold plate liquid cooling system according to claim 21, characterized in that: The two-phase cold plate liquid cooling system is configured as at least one of the following computer devices: GPU server, the front evaporator (33) is configured to cool the SW chip, and the first evaporator (31) and the second evaporator (32) are configured to cool the GPU; In a general server, the front evaporator (33) is configured to cool a VR chip, and the first evaporator (31) and the second evaporator (32) are configured to cool a CPU; Storage server, the front evaporator (33) is configured to cool the VR chip, and the first evaporator (31) and the second evaporator (32) are configured to cool the hard disk; The switch, the front evaporator (33) is configured to cool the optical module assembly, and the first evaporator (31) and the second evaporator (32) are configured to cool the SW chip.

23. A control method, characterized in that: The control method is used for the two-phase cold plate liquid cooling system according to any one of claims 1 to 22, and the control method comprises: The first evaporator (31) and the second evaporator (32) of the two-phase cold plate liquid cooling system cool different components respectively; According to the heat transfer requirements of the components cooled by the second evaporator (32), the gas-liquid rectifier (40) located between the first evaporator (31) and the second evaporator (32) is adjusted by at least one of the following operations: replenishing liquid refrigerant, replenishing gaseous refrigerant, discharging a portion of the liquid refrigerant, or discharging a portion of the gaseous refrigerant, so as to adjust the dryness of the refrigerant to enter the second evaporator (32).

24. The control method according to claim 23, characterized in that: The control method further includes: detecting the dryness E of the refrigerant output by the first evaporator (31), or detecting the dryness E of the refrigerant output by the gas-liquid rectifier (40); The heat transfer requirement of the component cooled by the second evaporator (32) is obtained based on its own power consumption, the mass flow rate of the refrigerant in the second evaporator (32), and the latent heat of vaporization of the refrigerant; The expected dryness of the second evaporator (32) to meet the heat transfer requirements of the components it cools is X. E is compared with X. When E is less than X, the dryness of the refrigerant is increased through the adjustment operation. When E is greater than X, the dryness of the refrigerant is reduced through the adjustment operation.

25. The control method according to claim 24, characterized in that: The adjustment operation is: In the case of E<X, the gaseous refrigerant is added to the gas-liquid rectifier (40), and in the case of E>X, the liquid refrigerant is added to the gas-liquid rectifier (40); or, In the case of E<X, a portion of the liquid refrigerant in the gas-liquid rectifier (40) is discharged, and in the case of E>X, the liquid refrigerant is replenished to the gas-liquid rectifier (40); or, When E<X, the gaseous refrigerant is added to the gas-liquid rectifier (40), and when E>X, a portion of the gaseous refrigerant in the gas-liquid rectifier (40) is discharged.

26. The control method according to claim 24, characterized in that: X=A*Q^b*V^c*H^d; Among them, Q is the power consumption of the components cooled by the second evaporator (32), in W; V is the mass flow rate of the refrigerant, in M / S; H is the latent heat of vaporization of the refrigerant, in KJ / KG; b, c, and d are indexes, and A is a correction coefficient; the range of B is 0.3 to 0.6, the range of c is 0.1 to 0.36, and the range of d is 0.01 to 0.

1.

27. The control method according to claim 23, characterized in that: The gas-liquid rectifier (40) includes a rectifier box (41) and a gas-liquid separator (47) located therein, wherein an inlet of the rectifier box (41) is connected to the first evaporator (31). The control method further includes: When a portion of the liquid refrigerant or a portion of the gaseous refrigerant in the gas-liquid rectifier (40) is discharged, the refrigerant input from the inlet of the rectifier tank (41) is subjected to gas-liquid separation by the gas-liquid separator (47); When the liquid refrigerant or the gaseous refrigerant in the gas-liquid rectifier (40) is not discharged, the gas-liquid separator (47) does not perform gas-liquid separation.

28. The control method according to claim 23, characterized in that: A front evaporator (33) is connected in series before the first evaporator (31), and the control method further includes: The front evaporator (33) cools low-power consumption components, and the first evaporator (31) and the second evaporator (32) cool different high-power consumption components respectively.

Images