A single-phase immersion liquid cooling thermal management system and method of use

Abstract

This invention belongs to the field of data center server heat dissipation technology, and particularly relates to a single-phase immersion liquid cooling thermal management system and its usage method. When the heat dissipation load is low, the system is in the first operating condition, and the coolant circulates only between the immersion cabinet and the cooling distribution unit. When the server load increases and the coolant temperature exceeds a set threshold, the system switches to the second operating condition, where the coolant flows through the immersion cabinet, the cooling distribution unit, and the dry cooler for enhanced heat exchange. When the ambient temperature is too low, causing the viscosity of the insulating coolant to increase, and thus the oil pressure at the inlet of the dry cooler exceeds a preset value, the second controller, electrically connected to the acquisition module, immediately controls the solenoid valve on the bypass pipe to open, establishing a bypass flow path to ensure uninterrupted coolant circulation, effectively preventing flow channel blockage, and significantly simplifying the system structure. The dry cooler bypass pipe design, combined with intelligent pressure control, ensures the reliability of the system's start-up and operation under extremely cold conditions.

Description

Technical Field

[0001] This invention belongs to the field of data center server heat dissipation technology, and particularly relates to a single-phase immersion liquid cooling thermal management system and its usage method. Background Technology

[0002] Liquid cooling technology, with its significantly higher heat transfer coefficient and lower energy consumption compared to air cooling, has become the mainstream development direction for data center heat dissipation. Immersion liquid cooling technology, in particular, involves directly immersing heat-generating electronic components in an insulating coolant, achieving efficient heat exchange through direct liquid contact. Immersion cooling can be divided into single-phase immersion and two-phase immersion. Single-phase immersion technology is favored due to its stable heat transfer performance, strong system controllability, flexible modular design, and ability to achieve extremely low PUE values.

[0003] However, existing technologies have the following problems: In application, existing single-phase immersion liquid cooling systems typically employ two independent heat exchange circuits on the primary and secondary sides. The primary side uses an insulating liquid circulation circuit, while the secondary side uses a solution such as ethylene glycol circulation, supplemented by a complex external circulation device. This dual heat exchange architecture results in a complex system structure and numerous pipelines, and its deployment cost is significantly higher than that of traditional air-cooled solutions, placing a heavy economic burden on users. At the same time, when the ambient temperature is below 0°C, the viscosity of the insulating coolant increases sharply, its fluidity decreases, and the resistance during flow increases, which may lead to blockage of the flow channels, causing the system to malfunction and reducing energy efficiency.

[0004] Therefore, a single-phase immersion liquid-cooled thermal management system and its usage method are proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a single-phase immersion liquid-cooled thermal management system and its usage method to solve the above-mentioned problems.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A single-phase immersion liquid-cooled thermal management system includes: an immersion cabinet, a cooling capacity distribution unit, and a dry cooler;

[0008] In the first operating condition, the coolant flows between the submerged cabinet and the cooling distribution unit;

[0009] In the second operating condition, the coolant flows between the submerged cabinet, the cooling capacity distribution unit, and the dry cooler;

[0010] A bypass pipe is connected in parallel between the oil inlet and the oil outlet of the dry cooler. A solenoid valve is installed on the bypass pipe. The solenoid valve is electrically connected to a second controller. The second controller is electrically connected to an acquisition module. The acquisition module is used to acquire the oil pressure at the oil inlet.

[0011] When the oil pressure at the oil inlet is greater than a preset value, the second controller controls the solenoid valve to open.

[0012] In the single-phase immersion liquid-cooled thermal management system of the present invention, the dry cooler further includes multiple vertical channels, which are arranged sequentially at intervals. Fins are provided on the vertical channels. The top of each of the multiple vertical channels is connected to an oil inlet channel, one end of the oil inlet channel is connected to an oil inlet, and the bottom ends of each of the multiple vertical channels are connected to an oil outlet channel. One end of the oil outlet channel is connected to an oil outlet. The acquisition module is located at the end of the oil inlet channel away from the oil inlet.

[0013] In the single-phase immersion liquid-cooled thermal management system of the present invention, a variable frequency fan is provided on one side of each of the multiple vertical channels.

[0014] In the single-phase immersion liquid-cooled thermal management system of the present invention, a heating section of a heater is provided in the oil inlet channel, and the heater is electrically connected to the second controller.

[0015] In the single-phase immersion liquid-cooled thermal management system of the present invention, the outlet end of the immersion cabinet is connected to the inlet of an electrically controlled three-way valve, one outlet of the electrically controlled three-way valve is connected to the oil inlet, the other outlet of the electrically controlled three-way valve is connected to the inlet end of the cooling capacity distribution unit, and the oil outlet is connected to the inlet end of the cooling capacity distribution unit.

[0016] In the single-phase immersion liquid-cooled thermal management system of the present invention, the cooling capacity distribution unit includes two parallel coolant drive components. The coolant drive components include a variable frequency water pump. The inlet of the variable frequency water pump is connected to the electrically controlled three-way valve and the oil outlet. The outlet of the variable frequency water pump is connected to a one-way valve. The one-way valve is connected to a filter tank. An automatic air vent valve is provided on the filter tank. The filter tank is connected to the inlet end of the immersion cabinet.

[0017] In the single-phase immersion liquid-cooled thermal management system of the present invention, a first pressure sensor and a first temperature sensor are sequentially arranged between the oil outlet, the electrically controlled three-way valve and the two variable frequency water pumps.

[0018] In the single-phase immersion liquid-cooled thermal management system of the present invention, a flow meter, a second pressure sensor, and a second temperature sensor are sequentially arranged between the two filter tanks and the inlet end of the immersion cabinet.

[0019] In the single-phase immersion liquid-cooled thermal management system of the present invention, a first valve is provided between the variable frequency water pump and the first temperature sensor, and a second valve is provided between the filter tank and the flow meter.

[0020] A method for using a single-phase immersion liquid-cooled thermal management system, based on the aforementioned single-phase immersion liquid-cooled thermal management system, comprises the following steps:

[0021] Once the coolant temperature is determined to be lower than the preset value, the system is in its first operating condition. Under the drive of the cooling distribution unit, the coolant circulates between the immersion cabinet and the cooling distribution unit.

[0022] Once the coolant temperature is determined to be greater than the preset value, the system enters the second operating condition. Under the drive of the cooling capacity distribution unit, the coolant circulates between the immersion cabinet, the cooling capacity distribution unit, and the dry cooler.

[0023] The second controller controls the solenoid valve to open when the oil pressure at the inlet is determined by the acquisition module and the oil pressure at the inlet is greater than the preset value.

[0024] Compared with the prior art, the present invention has the following advantages and technical effects:

[0025] When the heat dissipation load is low, the system operates in the first mode, with the coolant circulating only between the immersion cabinet and the cooling distribution unit. When the server load increases, causing the coolant temperature to exceed a set threshold, the system switches to the second mode, where the coolant flows through the immersion cabinet, the cooling distribution unit, and the dry cooler for enhanced heat exchange. Its core protection mechanism is as follows: when the ambient temperature is too low, causing the viscosity of the insulating coolant to increase and the oil pressure at the dry cooler's inlet to exceed a preset value, the second controller, electrically connected to the acquisition module, immediately controls the solenoid valve on the bypass pipe to open, establishing a bypass flow path to ensure uninterrupted coolant circulation and effectively prevent flow channel blockage.

[0026] The advantages of this invention are as follows: by replacing the traditional dual independent heat exchange loops with a single-loop design, the system structure is significantly simplified, and initial investment and deployment costs are reduced; the dry cooler bypass pipe design combined with intelligent pressure control overcomes the technical bottleneck of poor coolant flow in low-temperature environments, ensuring the system's start-up and operational reliability under frigid conditions and broadening its application range. This integrated solution achieves energy consumption optimization and a comprehensive improvement in system reliability while ensuring efficient heat dissipation. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort:

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 This is a schematic diagram of the dry cooler in this invention;

[0030] The components include: 1. Immersion cabinet; 2. Server; 3. Third temperature sensor; 4. Electrically controlled three-way valve; 5. Dry cooler; 6. Variable frequency fan; 7. First pressure sensor; 8. First temperature sensor; 9. First valve; 10. Variable frequency water pump; 11. Check valve; 12. Automatic exhaust valve; 13. Filter tank; 14. Second valve; 15. Flow meter; 16. Second pressure sensor; 17. Second temperature sensor; 501. Heater; 502. Oil inlet; 503. Oil inlet channel; 504. Oil pressure sensor; 505. Fins; 506. Oil outlet; 507. Oil outlet channel; 508. Vertical channel; 509. Solenoid valve; 510. Second controller; 511. Bypass pipe. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Reference Figures 1 to 2 The present invention discloses a single-phase immersion liquid-cooled thermal management system, comprising: an immersion cabinet 1, a cooling capacity distribution unit, and a dry cooler 5;

[0034] In the first operating condition, the coolant flows between the submerged cabinet 1 and the cooling distribution unit;

[0035] In the second operating condition, the coolant flows between the submerged cabinet 1, the cooling distribution unit, and the dry cooler 5;

[0036] A bypass pipe 511 is connected in parallel between the oil inlet 502 and the oil outlet 506 of the dry cooler 5. A solenoid valve 509 is installed on the bypass pipe 511. The solenoid valve 509 is electrically connected to a second controller 510. The second controller 510 is electrically connected to an acquisition module. The acquisition module is used to acquire the oil pressure at the oil inlet 502.

[0037] When the oil pressure at the oil inlet 502 is greater than the preset value, the second controller 510 controls the solenoid valve 509 to open.

[0038] Server 2 is placed inside the immersion cabinet 1 and is completely submerged in coolant. The acquisition module includes oil pressure sensor 504.

[0039] In the first operating condition, the coolant circulates only between the submerged cabinet 1 and the cooling distribution unit, suitable for low loads or suitable ambient temperatures. When the heat dissipation demand increases, the system switches to the second operating condition, where the coolant flows through the dry cooler 5 for enhanced heat exchange. When the oil pressure at the oil inlet 502 exceeds the preset value due to the increased viscosity of the liquid at low temperatures, the second controller 510 immediately opens the solenoid valve 509 on the bypass pipe 511 to establish a bypass flow path, effectively preventing flow channel blockage. As the coolant temperature increases, the portion of the coolant whose viscosity has increased due to low temperatures gradually decreases in viscosity and resumes flow under the action of the remaining high-temperature coolant. At this time, the solenoid valve 509 closes. This setting ensures the reliability of the system in extremely cold environments, thereby solving the core problem of poor low-temperature adaptability of traditional liquid cooling systems.

[0040] A third temperature sensor 3 is installed at the outlet of the immersion cabinet 1.

[0041] In one alternative embodiment, the dry cooler 5 further includes multiple vertical channels 508 arranged sequentially at intervals. Each vertical channel 508 is provided with fins 505. The top ends of each vertical channel 508 are connected to an oil inlet channel 503. One end of the oil inlet channel 503 is connected to an oil inlet 502. The bottom ends of each vertical channel 508 are connected to an oil outlet channel 507. One end of the oil outlet channel 507 is connected to an oil outlet 506. The acquisition module is located at the end of the oil inlet channel 503 away from the oil inlet 502.

[0042] After the coolant enters the oil inlet channel 503 through the oil inlet 502, it is distributed into multiple spaced vertical channels 508, increasing the contact area with air. An oil pressure sensor, acting as a data acquisition module, is located at the end of the oil inlet channel 503. It detects the increase in total system pressure caused by the simultaneous deterioration of flow at the inlets of the multiple vertical channels 508, thereby triggering a bypass mechanism in a timely manner, optimizing control response speed and heat exchange efficiency.

[0043] In one alternative, a variable frequency fan 6 is provided on one side of multiple vertical channels 508.

[0044] The variable frequency fan 6 operates at high speed during high-temperature periods or under high load to enhance cooling, and at low speed or stops during low-temperature periods or under low load to utilize natural cooling sources, achieving precise matching of cooling capacity and a significant reduction in fan energy consumption.

[0045] In one alternative, a heating section of a heater 501 is provided in the oil inlet channel 503, and the heater 501 is electrically connected to the second controller 510.

[0046] When the second controller 510 determines that the ambient temperature is low based on the increase in oil pressure, it activates the heater 501 at the same time as starting the bypass to locally heat the high-viscosity coolant, effectively reducing its viscosity and assisting in clearing the vertical channel 508. Together with the bypass mechanism, they work to ensure the stability of the system's start-up and operation under extremely cold conditions.

[0047] In one alternative, the outlet of the immersion cabinet 1 is connected to the inlet of an electrically controlled three-way valve 4, one outlet of the electrically controlled three-way valve 4 is connected to an oil inlet 502, the other outlet of the electrically controlled three-way valve 4 is connected to the inlet of a cooling distribution unit, and the oil outlet 506 is connected to the inlet of the cooling distribution unit.

[0048] When the coolant temperature is low, the electrically controlled three-way valve 4 guides the liquid directly back to the cooling capacity distribution unit, forming an internal circulation. When the temperature rises, the flow path is switched so that the liquid flows to the oil inlet 502 of the dry cooler 5 for cooling.

[0049] In one alternative embodiment, the cooling capacity distribution unit includes two parallel coolant drive components. Each coolant drive component includes a variable frequency water pump 10. The inlet of the variable frequency water pump 10 is connected to an electrically controlled three-way valve 4 and an oil outlet 506. The outlet of the variable frequency water pump 10 is connected to a one-way valve 11. The one-way valve 11 is connected to a filter tank 13. An automatic air vent valve 12 is installed on the filter tank 13. The filter tank 13 is connected to the inlet end of the immersion cabinet 1.

[0050] The coolant drive assembly consists of a variable frequency water pump 10, a one-way valve 11, and a filter tank 13 arranged in sequence. Two sets of coolant drive assemblies are connected in parallel to form a redundant backup. When one set requires maintenance, the other set can continue to work, ensuring uninterrupted system operation. The variable frequency water pump 10 enables precise flow regulation and matching with the heat dissipation load.

[0051] In one alternative scheme, a first pressure sensor 7 and a first temperature sensor 8 are sequentially installed between the oil outlet 506, the electrically controlled three-way valve 4, and the two variable frequency water pumps 10.

[0052] The return temperature monitored by the first temperature sensor 8 is the core basis for judging the operating conditions and switching the electric three-way valve 4; the first pressure sensor 7 monitors the pressure in front of the pump in real time, providing a guarantee for the safe operation and fault diagnosis of the variable frequency water pump 10.

[0053] In one alternative configuration, a flow meter 15, a second pressure sensor 16, and a second temperature sensor 17 are sequentially arranged between the two filter tanks 13 and the inlet end of the immersion chamber 1.

[0054] The flow meter 15, the second pressure sensor 16, and the second temperature sensor 17 work together to accurately monitor the flow rate, pressure, and temperature of the coolant entering the immersion tank 1, providing a complete data foundation for evaluating the heat dissipation effect, optimizing the operating frequency of the variable frequency water pump 10, and realizing closed-loop intelligent control of the entire system.

[0055] In one alternative, a first valve 9 is provided between the variable frequency water pump 10 and the first temperature sensor 8, and a second valve 14 is provided between the filter tank 13 and the flow meter 15.

[0056] When it is necessary to replace or repair components such as the variable frequency water pump 10 and the filter tank 13, the corresponding valves can be closed to isolate them from the system, without having to drain the coolant from the entire circuit, which significantly reduces maintenance difficulty and time costs.

[0057] A method for using a single-phase immersion liquid-cooled thermal management system, based on the single-phase immersion liquid-cooled thermal management system, includes the following steps:

[0058] When the coolant temperature is determined to be lower than the preset value, the first working condition is reached. The coolant circulates between the immersion cabinet 1 and the coolant distribution unit under the drive of the cooling distribution unit.

[0059] When the coolant temperature is determined to be greater than the preset value, the second working condition is entered. The coolant circulates between the immersion cabinet 1, the coolant distribution unit and the dry cooler 5 under the drive of the cooling capacity distribution unit.

[0060] The second controller 510 controls the solenoid valve 509 to open when the oil pressure at the oil inlet 502 is determined by the acquisition module to be greater than the preset value.

[0061] Operating Process: The server 2, completely submerged in insulating coolant inside the immersion cabinet 1, generates heat, which heats the surrounding coolant. The heated coolant flows out from the outlet of the immersion cabinet 1. A third temperature sensor 3 at this location monitors the outlet temperature in real time; this temperature is one of the core parameters for the system to determine operating conditions and perform intelligent switching. The outflowing coolant enters the inlet of the electrically controlled three-way valve 4. The system determines the operating mode based on the readings of the third temperature sensor 3 and the subsequent first temperature sensor 8: When the coolant temperature is lower than the preset value, it indicates that the heat dissipation demand is low or the ambient temperature is suitable, and the system is in the first operating condition. At this time, the electrically controlled three-way valve 4 switches to the internal circulation path, and its outlet is directly connected to the inlet of the cooling capacity distribution unit, allowing the coolant to bypass the dry cooler 5 and circulate only between the immersion cabinet 1 and the cooling capacity distribution unit, fully utilizing the liquid's own heat capacity and the cabinet surface for heat dissipation, thereby maximizing energy savings.

[0062] When the load on server 2 increases, causing the coolant temperature to exceed a preset threshold, the system automatically switches to the second operating mode. At this time, the electrically controlled three-way valve 4 changes the flow path, connecting its outlet to the oil inlet 502 of the dry cooler 5. The high-temperature coolant then enters the oil inlet channel 503 of the dry cooler 5. Under normal conditions, i.e., when the ambient temperature is high and the coolant viscosity is normal, the liquid is evenly distributed from the oil inlet channel 503 into multiple vertical channels 508. These vertical channels 508 are equipped with air-cooled fins 505 on their outer walls, and the variable frequency fan 6 on one side adjusts its speed according to the cooling demand, forcing air to flow over the fin surface, carrying away heat, and achieving efficient heat exchange for the coolant. The cooled liquid collects in the oil outlet channel 507 and finally flows out from the oil outlet 506.

[0063] However, in frigid conditions with ambient temperatures below 0°C, the system demonstrates its crucial low-temperature adaptability. Low temperatures cause a sharp increase in coolant viscosity, leading to a surge in resistance as it flows through the narrow vertical channel 508, resulting in pressure buildup at the end of the inlet channel 503. At this point, the oil pressure sensor 504, acting as the acquisition module, detects this pressure value in real time. When the pressure exceeds a preset safety threshold, the second controller 510, electrically connected to it, immediately issues a command to open the solenoid valve 509 on the bypass pipe 511 connected in parallel between the inlet port 502 and the outlet port 506. Simultaneously, the second controller 510 activates the heating section of the heater 501 located within the inlet channel 503. The opening of the solenoid valve 509 instantly establishes a low-resistance bypass flow path, ensuring uninterrupted coolant circulation; while the activation of the heater 501 locally heats the flowing high-viscosity coolant, reducing its viscosity. The hot liquid flows downwards under gravity, helping to melt and clear any potential flow bottlenecks in the vertical channel 508. As localized heating and circulation continue, the flow of the vertical channel 508 gradually recovers, and the pressure in the oil inlet channel 503 decreases accordingly. When the oil pressure sensor 504 detects that the pressure has returned to the normal range, the second controller 510 closes the solenoid valve 509 and the heater 501, and the system returns to normal heat exchange mode through the vertical channel 508 and the air-cooled fins 505. This intelligent pressure response and thermal management mechanism ensures the system's start-up reliability and operational stability in extremely cold environments.

[0064] Coolant flowing from the oil outlet 506 of the dry cooler 5 or from the bypass path of the electrically controlled three-way valve 4 flows to the cooling capacity distribution unit. Here, a first pressure sensor 7 and a first temperature sensor 8, sequentially arranged in the pipeline, monitor the pressure and temperature of the returning liquid, providing data for subsequent control. The coolant then enters the cooling capacity distribution unit, which consists of two sets of coolant drive components arranged in parallel. Each drive component includes a variable frequency water pump 10, a check valve 11, and a filter tank 13 with an automatic vent valve 12. The variable frequency water pump 10 serves as the core of the system's power, dynamically adjusting the flow rate according to heat dissipation requirements; the check valve 11 prevents liquid backflow; the filter tank 13 purifies the coolant; and the automatic vent valve 12 removes any gas that may accumulate in the system. This parallel redundancy design allows the corresponding first valve 9 and second valve 14 to be closed when one set of components requires maintenance, while the other set of components maintains system operation, ensuring high system availability.

[0065] Finally, driven by the cooling distribution unit, the coolant flows through the flow meter 15 for precise flow measurement, the second pressure sensor 16 for monitoring the inlet pressure, and the second temperature sensor 17 for monitoring the inlet temperature, before returning to the inlet of the immersion cabinet 1 to restart the circulation, continuously providing efficient and reliable cooling for the server 2. The entire system, through a sensor network and intelligent controller distributed at key nodes, achieves real-time monitoring of temperature, pressure, and flow, as well as precise control of actuators such as pumps, fans, and valves, thus achieving an optimal balance between high energy efficiency, high reliability, and wide temperature range adaptability.

[0066] Specific example: When the third temperature sensor 3 detects that the temperature of the coolant flowing out of the immersion cabinet 1 is less than or equal to 25°C, the system determines that it is under low heat load or can utilize natural cooling. At this time, the system controls the electrically controlled three-way valve 4 to switch to a bypass path without the dry cooler 5, allowing the coolant to flow directly back to the cooling capacity distribution unit. Simultaneously, the variable frequency water pump 10 in the cooling capacity distribution unit operates at a low frequency of 30Hz, providing the power required to maintain basic circulation. In this mode, the coolant circulates only within the loop formed by the immersion cabinet 1, the electrically controlled three-way valve 4, and the cooling capacity distribution unit, without flowing through the dry cooler 5. The variable frequency fan 6 does not start, and the system operates with minimal energy consumption, making full use of the coolant's own heat capacity and the heat dissipation from the cabinet surface.

[0067] When the load on server 2 increases, causing the outlet temperature detected by the third temperature sensor 3 to be greater than 25°C but not exceeding 35°C, and the ambient temperature is above 0°C, the system switches to external circulation mode. The electrically controlled three-way valve 4 changes the flow direction, guiding the higher-temperature coolant from the submerged cabinet 1 to the oil inlet 502 of the dry cooler 5. At this time, the variable frequency water pump 10 still operates at 30Hz. The coolant flows through the oil inlet channel 503, vertical channel 508, and air-cooled fins 505 of the dry cooler 5. Because the load is low at this time, heat dissipation relies solely on natural air convection or extremely low wind speed; the variable frequency fan 6 is usually not started or operates at an extremely low frequency. The cooled liquid flows out from the oil outlet 506 and returns to the cooling capacity distribution unit.

[0068] If the heat load continues to increase, the outlet liquid temperature rises to above 35℃ but not exceeding 46℃, and the ambient temperature is above 0℃, the system enters the active air-cooling stage. The electrically controlled three-way valve 4 remains open to the dry cooler 5, and the frequency of the variable frequency water pump 10 remains at 30Hz. To enhance heat dissipation, the system starts the variable frequency fan 6 and controls it to operate at a frequency of 30Hz to force ventilation of the air-cooled fins 505 of the dry cooler 5, thereby significantly improving the heat exchange capacity of the dry cooler 5 to meet the increased heat dissipation demand.

[0069] When the outlet liquid temperature rises further to above 46℃ but not exceeding 49℃, and the ambient temperature is above 0℃, the system further increases the cooling intensity. The electrically controlled three-way valve 4 and the variable frequency water pump 10 maintain a constant frequency of 30Hz. The system increases the operating frequency of the variable frequency fan 6 to 50Hz, i.e., operates at its highest speed, maximizing the air-side heat exchange efficiency of the dry cooler 5 and suppressing the outlet liquid temperature below the set threshold.

[0070] With continued heat dissipation demand, the coolant outlet temperature exceeds 49℃ but remains below 52℃, and the ambient temperature is above 0℃. The system will simultaneously increase the flow rate of the variable frequency water pump 10 and enhance the cooling capacity of the variable frequency fan 6. The electrically controlled three-way valve 4 remains connected to the dry cooler 5. The system will increase the operating frequency of the variable frequency water pump 10 from 30Hz to 50Hz to increase the coolant circulation flow rate; simultaneously, the variable frequency fan 6 will maintain its maximum operating frequency of 50Hz. This measure aims to maximize heat dissipation by simultaneously increasing both coolant flow rate and airflow, thereby preventing the temperature from rising further.

[0071] When the outlet liquid temperature exceeds 52℃ and the ambient temperature is above 0℃, the system maintains the power level required to keep the outlet liquid temperature above 49℃. If this state continues for more than 0.5 hours, the system will determine that its heat dissipation capacity has reached its limit, issue an alarm, and shut down server 2 to prevent overheating damage to the equipment.

[0072] When the dry cooler 5 is running and the ambient temperature is less than or equal to 0°C, the viscosity of the coolant increases due to the ambient temperature. The heater 501 in the oil inlet channel 503 of the dry cooler 5 is energized to preheat the coolant about to enter the vertical channel 508 for 0.5 hours. After heating, the heater 501 is turned off, and the variable frequency water pump 10 starts running at the lowest frequency. The system enters a special "low-temperature adaptation mode," continuously monitoring the outlet temperature: if the absolute value of the difference between the current outlet temperature and ten minutes ago is less than or equal to 5°C, and the outlet temperature is below 52°C, then only the variable frequency water pump 10 is maintained at the lowest frequency; if this condition is not met, while the variable frequency water pump 10 is running at the lowest frequency, the variable frequency fan 6 is also started at the lowest frequency, and temperature changes are continuously monitored until the system stabilizes. The core of this mode is to prevent the high-viscosity coolant from flowing poorly within the dry cooler 5 at low temperatures, achieving safe start-up and operation through heating and careful pump and fan control.

[0073] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0074] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A single-phase immersion liquid-cooled thermal management system, characterized in that, include: Submerged cabinet (1), cold distribution unit and dry cooler (5); In the first operating condition, the coolant flows between the submerged cabinet (1) and the cooling capacity distribution unit; In the second operating condition, the coolant flows between the submerged cabinet (1), the cooling capacity distribution unit, and the dry cooler (5); A bypass pipe (511) is connected in parallel between the oil inlet (502) and the oil outlet (506) of the dry cooler (5). A solenoid valve (509) is installed on the bypass pipe (511). The solenoid valve (509) is electrically connected to a second controller (510). The second controller (510) is electrically connected to an acquisition module. The acquisition module is used to acquire the oil pressure at the oil inlet (502). When the oil pressure at the oil inlet (502) is greater than the preset value, the second controller (510) controls the solenoid valve (509) to open; The outlet end of the immersion cabinet (1) is connected to the inlet of the electrically controlled three-way valve (4), one of the outlets of the electrically controlled three-way valve (4) is connected to the oil inlet (502), the other outlet of the electrically controlled three-way valve (4) is connected to the inlet end of the cooling capacity distribution unit, and the oil outlet (506) is connected to the inlet end of the cooling capacity distribution unit. The cooling capacity distribution unit includes two parallel coolant drive components. The coolant drive components include a variable frequency water pump (10). The inlet of the variable frequency water pump (10) is connected to the electronically controlled three-way valve (4) and the oil outlet (506). The outlet of the variable frequency water pump (10) is connected to a one-way valve (11). The one-way valve (11) is connected to a filter tank (13). An automatic exhaust valve (12) is provided on the filter tank (13). The filter tank (13) is connected to the inlet end of the immersion cabinet (1). The dry cooler (5) also includes multiple vertical channels (508), the top of each of the multiple vertical channels (508) is connected to the oil inlet channel (503), one end of the oil inlet channel (503) is connected to the oil inlet (502), and the oil inlet channel (503) is provided with a heating section of a heater (501); When the second controller (510) determines that the ambient temperature is low based on the increase in oil pressure, it activates the heater (501) at the same time as starting the bypass to locally heat the high viscosity coolant, effectively reducing its viscosity and assisting in clearing the vertical channel (508), working in synergy with the bypass mechanism.

2. The single-phase immersion liquid-cooled thermal management system according to claim 1, characterized in that: Multiple vertical channels (508) are arranged in sequence at intervals. Fins (505) are provided on the vertical channels (508). The bottom ends of the multiple vertical channels (508) are all connected to the oil outlet channel (507). One end of the oil outlet channel (507) is connected to the oil outlet (506). The acquisition module is located on the oil inlet channel (503) at the end away from the oil inlet (502).

3. A single-phase immersion liquid-cooled thermal management system according to claim 2, characterized in that: A variable frequency fan (6) is provided on one side of each of the multiple vertical channels (508).

4. A single-phase immersion liquid-cooled thermal management system according to claim 2, characterized in that: The heater (501) is electrically connected to the second controller (510).

5. A single-phase immersion liquid-cooled thermal management system according to claim 1, characterized in that: A first pressure sensor (7) and a first temperature sensor (8) are sequentially arranged between the oil outlet (506), the electrically controlled three-way valve (4), and the two variable frequency water pumps (10).

6. A single-phase immersion liquid-cooled thermal management system according to claim 5, characterized in that: A flow meter (15), a second pressure sensor (16), and a second temperature sensor (17) are sequentially arranged between the two filter tanks (13) and the inlet end of the immersion cabinet (1).

7. A single-phase immersion liquid-cooled thermal management system according to claim 6, characterized in that: A first valve (9) is provided between the variable frequency water pump (10) and the first temperature sensor (8), and a second valve (14) is provided between the filter tank (13) and the flow meter (15).

8. A method of using a single-phase immersion liquid-cooled thermal management system, based on the single-phase immersion liquid-cooled thermal management system according to any one of claims 1-7, characterized in that, The steps are as follows: When the coolant temperature is determined to be lower than the preset value, the first working condition is reached. The coolant circulates between the immersion cabinet (1) and the cooling distribution unit under the drive of the cooling distribution unit. When the coolant temperature is determined to be greater than the preset value, the second working condition is reached. The coolant circulates between the immersion cabinet (1), the coolant distribution unit and the dry cooler (5) under the drive of the cold energy distribution unit. The oil pressure at the oil inlet (502) is obtained by the acquisition module. When the oil pressure at the oil inlet (502) is greater than the preset value, the second controller (510) controls the solenoid valve (509) to open.

Images