Single-phase direct-cooling immersion liquid cooling device and control method

Abstract

This invention provides a single-phase direct-cooling immersion liquid cooling device and control method. The device fills the liquid cooling chamber with a high-boiling-point medium, and a direct-cooling plate is immersed within this medium. The direct-cooling plate, containing a low-boiling-point medium, is immersed in the high-boiling-point medium, creating a dual heat dissipation structure of phase change heat extraction and liquid temperature homogenization. This achieves balanced temperature control for multiple servers. The direct-cooling plate directly and efficiently absorbs heat from the server's heat source through phase change, and then dissipates the heat centrally through an external refrigeration unit. Simultaneously, the high-boiling-point medium, driven by a circulating pump, forms forced convection, effectively homogenizing the temperature throughout the liquid cooling chamber. This design not only avoids the localized overheating problem common in traditional immersion liquid cooling systems but also transfers the high heat flux density heat load through phase change in the low-boiling-point medium, significantly reducing the cooling power consumption during long-term system operation. Transferring heat through the low-boiling-point medium reduces the transport path of the high-boiling-point medium, lowering the risk of leakage.

Description

Technical Field

[0001] This invention belongs to the field of liquid cooling control technology, specifically relating to a single-phase direct-cooling immersion liquid cooling device and its control method. Background Technology

[0002] With the rapid development of artificial intelligence, the demand for computing power has surged, and data centers are evolving towards higher computing power. This high computing power brings with it the problem of high power consumption in servers, and traditional air cooling technology is struggling to meet the heat dissipation requirements of high-power-density servers. Against this backdrop, liquid cooling technology has rapidly developed due to its advantages such as high heat transfer coefficient and low energy consumption, aiming to significantly reduce the power utilization efficiency (PUE) of data centers. Data center liquid cooling can be divided into direct liquid cooling and indirect liquid cooling. Indirect liquid cooling mainly refers to cold plate liquid cooling, while direct liquid cooling mainly refers to immersion cooling, which typically involves immersing the server in an insulating liquid to cool it. However, current immersion liquid cooling methods are relatively simple, mainly relying on heat exchange between the primary and secondary sides of an external heat exchanger. This makes it impossible to balance the cooling based on the heat dissipation of multiple servers, resulting in the heat exchanger always being under high load and thus low heat exchange efficiency. Summary of the Invention

[0003] This invention provides a single-phase direct-cooling immersion liquid cooling device and control method, which aims to solve the problem that the heat exchange mode of the existing liquid cooling device is relatively simple and not easy to adjust flexibly.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is: to provide a single-phase direct-cooling immersion liquid cooling device, comprising: A liquid cooling chamber, the interior of which is equipped with a high-boiling-point medium, and multiple sets of servers are immersed in the high-boiling-point medium; A direct cooling plate is immersed in the high-boiling-point medium. The direct cooling plate contains a low-boiling-point medium. The top of the direct cooling plate is connected to an exhaust pipe, and the direct cooling plate is also connected to a liquid inlet pipe. A refrigeration unit, wherein the air inlet of the refrigeration unit is connected to the air outlet pipe, and the liquid outlet of the refrigeration unit is connected to the liquid inlet pipe; The circulation pipeline has an inlet end connected to the top of the liquid cooling chamber and an outlet end connected to the bottom of the liquid cooling chamber. A first circulation pump for circulating high-boiling-point media is connected to the circulation pipeline.

[0005] In one possible implementation, there are multiple direct cooling plates, which are arranged sequentially and at intervals inside the liquid cooling chamber, and adjacent direct cooling plates form an installation position for installing a server.

[0006] In one possible implementation, a drain pipe is arranged at the bottom of the liquid cooling chamber, the length direction of the drain pipe is arranged along the arrangement direction of the plurality of straight cooling plates, and a plurality of drain ports are arranged on the drain pipe, with a drain port provided below each of the mounting positions.

[0007] In one possible implementation, the cooling unit includes: The refrigeration pipeline has its two ends connected to the outlet pipe and the inlet pipe, respectively. The refrigeration pipeline is connected in sequence to a compressor, a condenser, a second circulation pump, and an expansion valve. A first control valve is connected in parallel to the pipeline corresponding to the compressor, and a second control valve is connected in parallel to the pipeline corresponding to the second circulation pump.

[0008] The solution described in this application, compared with the prior art, involves filling the liquid cooling chamber with a high-boiling-point medium and immersing a direct cooling plate within it. The direct cooling plate, containing a low-boiling-point medium, is submerged in the high-boiling-point medium, creating a dual heat dissipation structure of phase change heat extraction and liquid temperature homogenization, achieving balanced temperature control for multiple servers. The direct cooling plate directly and efficiently absorbs heat from the server's heat source through phase change, and centrally dissipates heat through an external refrigeration unit. Simultaneously, the high-boiling-point medium, driven by a circulating pump, forms forced convection, effectively homogenizing the temperature throughout the liquid cooling chamber. This design not only avoids the localized overheating problem common in traditional immersion liquid cooling but also transfers the high heat flux density heat load through phase change in the low-boiling-point medium, significantly reducing the cooling power consumption during long-term system operation. Transferring heat through the low-boiling-point medium reduces the transport path of the high-boiling-point medium, minimizing the risk of leakage. In addition, the independent dual-loop circuits form a flexible and adjustable heat dissipation system. By coordinating the adjustment of the power of the cooling unit and the liquid circulation flow rate, dynamic and refined management of the heat dissipation capacity of the entire system can be achieved, which significantly improves the system's adaptability and operational stability in response to different load conditions.

[0009] In conjunction with the first aspect, this application also provides a single-phase direct-cooling immersion liquid cooling control method, comprising the following steps: S1. After the server starts running, the first circulation pump is started first, and the temperature of the high-boiling-point medium on the circulation pipeline is monitored. S2. Define that when the temperature on the monitored circulation pipeline reaches a first threshold, the refrigeration unit is activated, wherein the first threshold is lower than the boiling point of the low-boiling-point medium.

[0010] In one possible implementation, when the refrigeration unit starts in step 2, the temperature at the liquid outlet of the liquid cooling unit is monitored, and a second threshold is defined as the compressor start-up threshold. At the same time, the ambient temperature outside the liquid cooling chamber is monitored. When the ambient temperature is less than the first threshold and the liquid outlet temperature of the liquid cooling unit is less than the second threshold, the compressor is in a stopped state.

[0011] In one possible implementation, in step 2, the compressor is started when the temperature at the outlet of the liquid cooling unit exceeds a second threshold or when the ambient temperature outside the liquid cooling chamber is greater than the liquid temperature in the circulation pipeline.

[0012] In one possible implementation, when the compressor is stopped, the operating state of the fan on the condenser is controlled by monitoring the temperature at the liquid outlet of the liquid cooling unit, and the fan start-up temperature is defined as a third threshold, which is less than the second threshold.

[0013] In one possible implementation, when monitoring the temperature at the liquid outlet of the liquid cooling unit, the temperature values ​​at multiple points are detected within a certain period of time, and the average of the maximum values ​​among the multiple temperature points is taken to obtain the monitored value. The monitored value is then compared with a second threshold and a third threshold.

[0014] In one possible implementation, the internal temperature of the server is monitored, and the difference between the internal temperature of the server and the liquid outlet temperature of the liquid cooling unit is taken. The standard value of the difference is defined as a fourth threshold. When the actual monitored difference is greater than the fourth threshold, the operating frequency of the cooling unit is increased.

[0015] Compared with the prior art, the solution shown in this application, combined with the above-mentioned device structure, prioritizes the activation of the first circulation pump. This first drives the high-boiling-point medium to establish a basic circulation and a uniform temperature field, providing a preliminary and balanced heat dissipation environment for the server and preventing localized heat accumulation. Subsequently, the cooling unit is activated only when the liquid temperature is detected to rise to a first threshold. This design ensures that the timing of the low-boiling-point medium's phase change heat absorption within the direct cooling plate precisely matches the system's heat load. This phased, condition-triggered activation strategy ensures that the cooling unit does not operate ineffectively under low heat loads, thereby significantly reducing system standby and low-load power consumption and extending the lifespan of core equipment. Furthermore, by pre-uniforming the high-boiling-point medium, it creates conditions for the stable and efficient operation of subsequent phase change cooling, enabling the entire system to adaptively adjust according to actual heat dissipation needs. This ensures effective heat dissipation while optimizing energy consumption and enhancing operational economy and reliability. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a single-phase direct-cooling immersion liquid cooling device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the refrigeration unit provided in an embodiment of the present invention; Figure 3 A flowchart of a single-phase direct-cooling immersion liquid cooling control method provided in an embodiment of the present invention.

[0017] Explanation of reference numerals in the attached figures: 1. Liquid cooling chamber; 2. Direct cooling plate; 3. Refrigeration unit; 31. Refrigeration piping; 32. Compressor; 33. Condenser; 331. Fan; 332. Expansion valve; 34. Second circulation pump; 35. First control valve; 36. Second control valve; 4. Circulation piping; 41. Drain pipe; 5. First circulation pump; 6. Server. Detailed Implementation

[0018] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0019] Please refer to the following: Figures 1 to 3 The single-phase direct-cooling immersion liquid cooling device provided by the present invention will now be described. The single-phase direct-cooling immersion liquid cooling device includes a liquid cooling chamber 1 and a direct-cooling plate 2 installed inside the liquid cooling chamber 1. A refrigeration unit 3 is provided on the outside of the liquid cooling chamber 1 to reduce the temperature of the medium inside the direct-cooling plate 2, and a circulation pipeline 4 for circulating the internal medium is also provided on the liquid cooling chamber 1. The liquid cooling chamber 1 contains a high-boiling-point medium, and multiple sets of servers 6 are immersed in the high-boiling-point medium. The direct-cooling plate 2 is immersed in the high-boiling-point medium, and contains a low-boiling-point medium. An exhaust pipe is connected to the top of the direct-cooling plate 2, and a liquid inlet pipe is also connected to the direct-cooling plate 2. The exhaust end of the refrigeration unit 3 is connected to the exhaust pipe, and the liquid outlet end of the refrigeration unit 3 is connected to the liquid inlet pipe. The liquid inlet end of the circulation pipeline 4 is connected to the top of the liquid cooling chamber 1, and the liquid outlet end is connected to the bottom of the liquid cooling chamber 1. A first circulation pump 5 for circulating the high-boiling-point medium is connected to the circulation pipeline 4.

[0020] The single-phase direct-cooling immersion liquid cooling device provided in this embodiment, compared with the prior art, fills the liquid cooling chamber 1 with a high-boiling-point medium, and immerses the direct-cooling plate 2 inside the high-boiling-point medium. The direct-cooling plate 2, with its built-in low-boiling-point medium, is immersed in the high-boiling-point medium, constructing a dual heat dissipation structure of phase change heat extraction and liquid temperature homogenization, achieving balanced temperature control for multiple servers 6. The direct-cooling plate 2 directly and efficiently absorbs heat from the heat source of the server 6 through phase change, and achieves centralized heat dissipation through the external cooling unit 3; simultaneously, the high-boiling-point medium forms forced convection under the drive of the circulating pump, effectively homogenizing the temperature throughout the liquid cooling chamber 1. This design not only avoids the local overheating problem common in traditional immersion liquid cooling, but also transfers the high heat flux density heat load through the phase change of the low-boiling-point medium, significantly reducing the cooling power consumption of the system during long-term operation. Transferring heat through the low-boiling-point medium reduces the transport path of the high-boiling-point medium, reducing the risk of leakage. In addition, the independent dual-loop circuits form a flexible and adjustable heat dissipation system. By coordinating the adjustment of the power of the refrigeration unit 3 and the liquid circulation flow rate, dynamic and refined management of the heat dissipation capacity of the entire system can be achieved, which significantly improves the system's adaptability and operational stability in response to different load conditions.

[0021] In some embodiments, the aforementioned direct cooling plate 2 can be adopted as follows: Figure 1 , Figure 2 The structure shown. See also... Figure 1 , Figure 2 Multiple direct cooling plates 2 are arranged sequentially and at intervals inside the liquid cooling chamber 1, with adjacent direct cooling plates 2 forming mounting positions for the server 6. The length direction of the liquid cooling chamber 1 is defined as the first direction, and the multiple direct cooling plates 2 are arranged at intervals along this first direction. The spacing between two adjacent direct cooling plates 2 is determined according to the size of the server 6, maintaining a small gap between the direct cooling plate 2 and the server 6. This also ensures that direct cooling plates 2 are installed on both sides of the server 6.

[0022] Specifically, in this embodiment, a highly efficient and collaborative heat dissipation architecture is formed between the server 6 and the direct cooling plate 2. Multiple direct cooling plates 2 are flexibly arranged along the length of the liquid cooling chamber 1, and the spacing between adjacent plates is precisely adjusted according to the size of the server 6, allowing each server 6 to be embedded in a heat dissipation compartment composed of two direct cooling plates 2. This layout ensures that both sides of the server 6 maintain minimal distance from the high-heat-exchange-efficiency direct cooling plates 2, effectively achieving enhanced heat exchange from the server to the high-boiling-point medium and then to the direct cooling plate 2. This not only significantly eliminates the temperature gradient that may be formed on both sides of the server 6 due to structural or power differences, but also allows the phase change heat absorption effect of the low-boiling-point medium to cover the main heat-generating areas of the server 6 without any blind spots, thereby constructing a rapidly responsive temperature field at the system level. Simultaneously, the flexible and adjustable spacing allows the device to adapt to servers 6 of different specifications, improving the system's versatility and deployment density.

[0023] In some embodiments, the liquid cooling chamber 1 described above can be as follows: Figure 1 , Figure 2 The structure shown. See also... Figure 1 , Figure 2 A drain pipe 41 is arranged at the bottom of the liquid cooling chamber 1. The length direction of the drain pipe 41 is along the arrangement direction of the multiple straight cooling plates 2, and multiple drain ports are arranged on the drain pipe 41, with a drain port located below each installation position. The length direction of the drain pipe 41 is along the arrangement direction of the multiple straight cooling plates 2, and multiple drain pipes 41 are arranged at intervals and parallel to each other at the bottom of the liquid cooling chamber 1. At the same time, the liquid outlet end of the circulation pipe 4 is connected to the multiple drain pipes 41, and the height of the liquid inlet end of the circulation pipe 4 is higher than the height of the multiple straight cooling plates 2.

[0024] Specifically, in this embodiment, the drain pipe 41 is arranged along the length of the direct cooling plate 2 and precisely aligned with the drain ports of each server 6 mounting position, effectively forming a bottom-directed flow diversion and turbulence system during operation. When the high-boiling-point liquid is driven by the first circulation pump 5, these drain ports located directly below the heat source can efficiently capture and drain the relatively high-temperature liquid accumulated at the bottom of the server 6 due to natural convection or localized heating, thus breaking the situation where a high-temperature stagnation layer or flow dead zone easily forms at the bottom of the traditional liquid cooling chamber 1. This design forcibly establishes a directional low-temperature liquid replenishment channel from the bottom of each heating unit outward, significantly enhancing the overall convective heat transfer intensity of the high-boiling-point liquid in both the vertical and horizontal directions. As a result, the heat generated by the server 6 is transported to the upper space and circulation pipe 4 more quickly and evenly, not only improving the temperature uniformity of the high-boiling-point liquid itself, but also indirectly enhancing the phase change heat absorption effect of the low-boiling-point medium in the direct cooling plate 2 by reducing the liquid base temperature in the contact area with the direct cooling plate 2. Therefore, the layout of the drain pipe 41 optimizes the heat flow path from the bottom layer of the system and works in conjunction with the aforementioned heat dissipation architecture to achieve dynamic balance of the temperature field of the entire chamber and global maximization of heat exchange efficiency.

[0025] In some embodiments, the refrigeration unit 3 described above may employ, for example... Figure 1 , Figure 2 The structure shown. See also... Figure 1 , Figure 2The refrigeration unit 3 includes a refrigeration pipe 31 and a compressor 32, a condenser 33, a second circulation pump 34, and an expansion valve 332 arranged on the refrigeration pipe 31. The two ends of the refrigeration pipe 31 are connected to an outlet pipe and a liquid inlet pipe, respectively. The compressor 32, the condenser 33, and the second circulation pump 34 are sequentially connected to the refrigeration pipe 31. A first control valve 35 is connected in parallel to the pipe corresponding to the compressor 32, and a second control valve 36 is connected in parallel to the pipe corresponding to the second circulation pump 34. The refrigeration pipe 31 forms the external circulation pipe 4 of the liquid cooling chamber 1. The compressor 32, the condenser 33, and the second circulation pump 34 are connected in series on the refrigeration pipe 31. It can adapt to various cooling modes according to the ambient temperature and the heat dissipation temperature of the server 6 inside the liquid cooling chamber 1.

[0026] Specifically, in this embodiment, when a stronger cooling effect is required, the compressor 32 and the condenser 33 can be turned on simultaneously, and the second circulation pump 34 can be used to accelerate the flow rate of the low-boiling-point medium to achieve a high-efficiency heat exchange effect. When the ambient temperature is low, the compressor 32 can be turned off and the second circulation pump 34 can be used alone, or a cooling method combining the circulation pump and the condenser 33 can be used, which can save energy and reduce consumption.

[0027] Specifically, in this embodiment, a first control valve 35 is connected in parallel to the pipeline corresponding to the compressor 32. The inlet end of the first control valve 35 is connected to the inlet end of the compressor 32, and the outlet end of the first control valve 35 is connected to the outlet end of the compressor 32. When the first control valve 35 is open, the low-boiling-point medium can flow through the first control valve 35 in the refrigeration pipeline 31, and the compressor 32 is in a stopped state. When the compressor 32 is in the working state, the first control valve 35 is closed, allowing the low-boiling-point medium to flow through the compressor 32 in the refrigeration pipeline 31.

[0028] Specifically, in this embodiment, a second control valve 36 is connected in parallel to the pipeline corresponding to the second circulation pump 34. The inlet end of the second control valve 36 is connected to the inlet end of the second circulation pump 34, and the outlet end of the second control valve 36 is connected to the outlet end of the second control valve 36. When the second control valve 36 is open, the low-boiling-point medium can flow through the second control valve 36 into the refrigeration pipeline 31, maintaining a stable flow rate inside the refrigeration pipeline 31 to ensure the flow of the low-temperature medium. When the second circulation pump 34 is adjusted to the working state, the second control valve 36 is closed, which can accelerate the flow rate of the liquid and improve the heat exchange effect. At the same time, an expansion valve 332 is also installed at the outlet end of the circulation pipeline 4. The expansion valve 332 can throttle and reduce the pressure and regulate the flow rate of the high-pressure liquid low-boiling-point medium.

[0029] Based on the same inventive concept, this application also provides a single-phase direct-cooling immersion liquid cooling control method, see [link to relevant documentation]. Figure 3 This includes the following steps: S1. After server 6 is running, the first circulation pump 5 is started first, and the temperature of the high-boiling-point medium on circulation pipeline 4 is monitored. S2. Define that when the temperature on the monitored circulation pipeline 4 reaches the first threshold, the refrigeration unit 3 is activated, wherein the first threshold is lower than the boiling point of the low-boiling-point medium.

[0030] Compared with the prior art, the solution shown in this application, combined with the above-mentioned device structure, prioritizes the activation of the first circulation pump 5. This first drives the high-boiling-point medium to establish a basic circulation and uniform temperature field, providing a preliminary and balanced heat dissipation environment for the server 6 and preventing localized heat accumulation. Subsequently, the cooling unit 3 is activated only when the liquid temperature is detected to rise to a first threshold. This design ensures that the timing of the low-boiling-point medium's phase change heat absorption within the direct cooling plate 2 precisely matches the system's heat load. This phased, condition-triggered activation strategy ensures that the cooling unit 3 does not need to operate ineffectively under low heat loads, thereby significantly reducing system standby and low-load power consumption and extending the lifespan of core equipment. Furthermore, by pre-uniforming the high-boiling-point medium, it creates conditions for the stable and efficient operation of subsequent phase change cooling, enabling the entire system to adaptively adjust according to actual heat dissipation needs. This ensures heat dissipation while optimizing energy consumption and enhancing operational economy and reliability.

[0031] Specifically, in this embodiment, the first threshold is lower than the boiling point of the low-boiling-point medium, but close to it, for example, 2 to 5 degrees lower than the boiling point of the low-boiling-point medium, thereby increasing the activation of the cooling unit before the low-boiling-point medium undergoes phase change.

[0032] Specifically, in this embodiment, when the refrigeration unit 3 starts in step 2, the temperature at the liquid outlet of the liquid cooling unit is monitored. A second threshold is defined as the starting threshold for the compressor 32. Simultaneously, the ambient temperature outside the liquid cooling chamber 1 is monitored. When the ambient temperature is lower than the first threshold and the liquid outlet temperature is lower than the second threshold, the compressor 32 is in a stopped state. The precise conditional start-stop control of the compressor 32 in step S2 further achieves refined optimization of system energy efficiency and a significant extension of the lifespan of core equipment. This control method creatively integrates the utilization of natural cold sources with the active cooling system by introducing ambient temperature and the liquid outlet temperature of the refrigeration unit 3 as dual judgment criteria. Specifically, when the external ambient temperature is sufficiently low (below the first threshold) and the liquid outlet temperature of the refrigeration unit 3 after preliminary heat exchange is also sufficiently low (below the second threshold), the system determines that the current natural cooling capacity has fully met or exceeded the heat dissipation requirements, thereby keeping the compressor 32 in a stopped state. This allows the entire system to maximize the use of natural cooling sources during transitional seasons or in low-temperature environments, ensuring that the core high-energy-consuming component, compressor 32, only starts operating when the actual heat load exceeds the natural cooling capacity. This control strategy not only significantly reduces the system's total energy consumption throughout the year but also effectively reduces mechanical wear and the risk of failure by minimizing the ineffective and low-load operating time of compressor 32. Ultimately, this design, while ensuring reliable heat dissipation, intelligently adapts the system's operating mode to environmental conditions, achieving a shift from on-demand cooling to utilizing external environmental conditions for cooling, resulting in multiple improvements in energy saving, economy, and reliability.

[0033] Specifically, in this embodiment, in step 2, the compressor 32 is started when the temperature at the outlet of the liquid cooling unit exceeds a second threshold or when the ambient temperature outside the liquid cooling chamber 1 is greater than the liquid temperature inside the circulation pipe 4. This control strategy constructs an intelligent and efficient start-stop criterion for the compressor 32 by dynamically linking the internal thermal state of the system with the external environmental conditions. When the temperature at the outlet of the refrigeration unit 3 is detected to be higher than the set threshold, it indicates that the current heat load of the system has exceeded the heat dissipation capacity of natural cooling and primary circulation, and the compressor 32 must be started to enhance the cooling power; while when the ambient temperature is higher than the liquid temperature inside the circulation pipe 4, it means that the external environment no longer has the conditions for natural cooling, and may even become a heat source, so the compressor 32 must also be started to ensure the cooling effect. This dual-condition triggering mechanism enables the system to respond to changes in the internal and external thermal environments in real time, achieving seamless switching and optimal matching between natural cooling and active cooling. The result not only ensures that the heat dissipation requirements of server 6 are absolutely met, but more importantly, it maximizes the potential of natural cold sources under different climatic conditions throughout the year, and only uses high-energy-consuming compressor 32 for cooling when necessary, thereby significantly reducing the overall operating energy consumption and electricity costs of the system, while also reducing the cumulative operating time of compressor 32.

[0034] Optionally, in this embodiment, when the compressor 32 is off, the operating state of the fan 331 on the condenser 33 is controlled by monitoring the liquid outlet temperature of the liquid cooling unit, and the start-up temperature of the fan 331 is defined as a third threshold, which is lower than the second threshold. When the compressor 32 is off, the start-up and stop control of the fan 331 on the condenser 33 is precisely correlated with the liquid outlet temperature of the refrigeration unit 3, and a third threshold lower than the start-up threshold of the compressor 32 is set. When the liquid outlet temperature of the liquid cooling unit is higher than the third threshold, the power of the fan 331 is increased to improve the cooling effect.

[0035] Specifically, when the ambient temperature is low enough that the compressor 32 does not need to be started, the system may still use the forced ventilation of the condenser 33 and the fan 331 to utilize ambient air for auxiliary heat dissipation of the working fluid circulating in the refrigeration unit 3 loop. Setting a lower third threshold as the start point for the fan 331 means that the system will only start this low-power auxiliary device, the fan 331, when it is confirmed that natural convection cooling is insufficient to maintain the outlet temperature below this preset optimized temperature. This ensures that the system temperature can still be controlled at a more ideal and safer lower level in pure natural cooling mode, while avoiding the ineffective operation of the fan 331 when the heat dissipation demand is extremely low.

[0036] This design enables the system to achieve heat dissipation at a near-low-load active cooling level with extremely low energy consumption, even when compressor 32 is off and fan 331 is on, effectively expanding the efficient operating range of the natural cooling mode. Ultimately, through stepped collaborative control of compressor 32, fan 331, and natural cooling based on multiple temperature thresholds, the system can automatically select the optimal energy-efficient heat dissipation combination strategy across the entire load range from low to high, thereby minimizing overall system power consumption while ensuring reliable heat dissipation.

[0037] Specifically, in this embodiment, when monitoring the temperature at the liquid outlet of the liquid cooling unit, the temperature values ​​at multiple points are detected within a certain time period. The average of the maximum values ​​among the multiple temperature points is taken to obtain the monitored value, which is then compared with the second and third thresholds. In the specific implementation of the control logic, the system adopts a highly reliable method based on multi-point sampling and optimization processing to monitor the temperature at the liquid outlet of the refrigeration unit 3: the system continuously collects real-time data from multiple temperature points within a set time period, such as 30 seconds, and then selects the highest values ​​from these data, such as the top 5 highest values; and calculates their average value. The monitored value obtained is used as the final basis for comparison with the preset second and third thresholds. This method effectively avoids equipment erroneous start-up or delayed start-up caused by local and short-term temperature fluctuations by eliminating instantaneous low-temperature interference and focusing on representative high points of thermal trends, ensuring the accuracy of the start-stop control decisions of the compressor 32 and the fan 331 and the stability of the overall system operation.

[0038] In some possible embodiments, by monitoring the internal temperature of server 6 and taking the difference between the internal temperature of server 6 and the temperature at the outlet of the liquid cooling unit, a standard value for the difference is defined as a fourth threshold. When the actual monitored difference is greater than the fourth threshold, the operating frequency of the cooling unit 3 is increased. Increasing the operating frequency of the cooling unit 3 includes increasing the operating frequency of the second circulation pump 34, the compressor 32, and the fan 331 on the condenser 33. This monitoring and control method, by introducing the temperature difference between the internal temperature of server 6 and the temperature at the outlet of the refrigerant as a core control parameter, achieves precise feedforward control and active adaptation to the dynamic load of the heat dissipation system.

[0039] Preferably, in this embodiment, when the monitoring difference is less than the fourth threshold, it proves that the operating power of the refrigeration unit 3 is relatively saturated. Then, the operating power of the refrigeration unit 3 is reduced, and the start-up of the compressor 32 or the fan 331 is determined by comparing the liquid outlet of the liquid cooling unit with the second and third thresholds in step 2, thus forming a control closed loop.

[0040] Specifically, this difference directly reflects the real-time matching degree between the heat generation rate of server 6 and the current system heat dissipation capacity. When the actual difference exceeds the preset fourth threshold, it indicates that the core heat load of server 6 is rising rapidly or the existing heat dissipation capacity has become lagging. The system then synchronously increases the operating frequency of the second circulation pump 34, compressor 32, and condenser fan 331 in the cooling unit 3. This linkage acceleration based on the temperature difference signal enables the entire active cooling cycle, including the circulation speed of the low-boiling-point medium, the cooling power of compressor 32, and the condensation heat dissipation intensity, to be enhanced immediately and synergistically. This rapidly increases the instantaneous cooling output of the system, bringing the temperature difference between server 6 and the system coolant back to the set range. This control strategy breaks through the delay of traditional feedback control that relies solely on a single temperature threshold. Through the temperature difference, a parameter directly related to "demand and supply," it achieves proactive response and suppression of heat load changes. This significantly improves the system's dynamic adjustment capability and thermal stability in response to sudden high loads on server 6 and in preventing temperature overshoot. While ensuring the safe operation of server 6, it also avoids energy waste caused by continuous high-frequency operation by precisely adjusting the power of each component as needed.

[0041] Specifically, in this embodiment, during the operation of compressor 32, if the actual difference exceeds the fourth threshold, the second control valve 36 is closed first, and the second circulation pump 34 is started to accelerate the circulation speed of the low-boiling-point medium. A fifth threshold for the difference is defined, which is greater than the fourth threshold. When the difference reaches the fifth threshold, the operating power of compressor 32, first circulation pump 5, and second circulation pump 34 is increased simultaneously. When the operating frequency of compressor 32, first circulation pump 5, and second circulation pump 34 has reached its maximum frequency, the average temperature at the liquid outlet of the liquid cooling unit is monitored for a period of time. If the difference between the average temperature and the average temperature of server 6 is still greater than the fourth threshold, the control unit alarms and shuts down or reduces the power of server 6. The power reduction of server 6 is stopped until the temperature difference is less than the fourth threshold. Thus, through a three-level progressive control of valve-pump coordination, system-wide frequency increase, and server 6 load reduction, the system's heat dissipation potential is maximized and server 6's stable operation is maintained while ensuring equipment safety.

[0042] Specifically, in this embodiment, in monitoring the liquid outlet of the liquid cooling unit and the internal temperature monitoring room of the server 6, multiple temperature points are monitored within N minutes, and the average of the M maximum temperatures is taken. The averaged temperature is then used as the current temperature value for comparison.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A single-phase direct-cooling immersion liquid cooling device, characterized in that, include: A liquid cooling chamber (1) is provided inside the liquid cooling chamber (1), and multiple servers (6) are immersed in the high boiling point medium. The direct cooling plate (2) is immersed in the high boiling point medium. The direct cooling plate (2) contains a low boiling point medium. The top of the direct cooling plate (2) is connected to an air outlet pipe, and the direct cooling plate (2) is also connected to a liquid inlet pipe. Refrigeration unit (3), wherein the air inlet of the refrigeration unit (3) is connected to the air outlet pipe, and the liquid outlet of the refrigeration unit (3) is connected to the liquid inlet pipe; The circulation pipeline (4) has an inlet end connected to the top of the liquid cooling chamber (1) and an outlet end connected to the bottom of the liquid cooling chamber (1). A first circulation pump (5) for circulating high-boiling-point media is connected to the circulation pipeline (4).

2. The single-phase direct-cooling immersion liquid cooling device as described in claim 1, characterized in that, There are multiple direct cooling plates (2), which are arranged sequentially and spaced apart inside the liquid cooling chamber (1), and the space between two adjacent direct cooling plates (2) forms an installation position for installing the server (6).

3. The single-phase direct-cooling immersion liquid cooling device as described in claim 2, characterized in that, The bottom of the liquid cooling chamber (1) is provided with a drain pipe (41), the length direction of which is arranged along the arrangement direction of the multiple straight cooling plates (2), and the drain pipe (41) is provided with multiple drain ports, and a drain port is provided below each of the installation positions.

4. The single-phase direct-cooling immersion liquid cooling device as described in claim 1, characterized in that, The refrigeration unit (3) includes: The refrigeration pipeline (31) is connected at both ends to the outlet pipe and the inlet pipe, respectively. The refrigeration pipeline (31) is connected in sequence to the compressor (32), the condenser (33), the second circulation pump (34) and the expansion valve (332). The compressor (32) is connected in parallel to the pipeline and the second circulation pump (34) is connected in parallel to the pipeline.

5. A single-phase direct-cooling immersion liquid cooling control method, employing the single-phase direct-cooling immersion liquid cooling device as described in any one of claims 1-4, characterized in that, Includes the following steps: S1. After the server (6) is running, the first circulation pump (5) is started first, and the temperature of the high-boiling-point medium on the circulation pipeline (4) is monitored. S2. When the temperature on the monitoring circulation pipeline (4) reaches the first threshold, the refrigeration unit (3) is started, wherein the first threshold is lower than the boiling point of the low boiling point medium.

6. The single-phase direct-cooling immersion liquid cooling control method as described in claim 5, characterized in that, In step 2, when the refrigeration unit (3) is started, the temperature at the liquid outlet of the liquid cooling unit is monitored. The second threshold is defined as the starting threshold of the compressor (32). At the same time, the ambient temperature outside the liquid cooling chamber (1) is monitored. When the ambient temperature is less than the first threshold and the liquid outlet temperature of the liquid cooling unit is less than the second threshold, the compressor (32) is in a stopped state.

7. The single-phase direct-cooling immersion liquid cooling control method as described in claim 6, characterized in that, In step 2, the compressor (32) is started when the temperature at the outlet of the liquid cooling unit exceeds the second threshold or when the ambient temperature outside the liquid cooling chamber (1) is greater than the liquid temperature inside the circulation pipe (4).

8. The single-phase direct-cooling immersion liquid cooling control method as described in claim 6, characterized in that, When the compressor (32) is stopped, the working state of the fan (331) on the condenser (33) is controlled by monitoring the liquid outlet temperature of the liquid cooling unit, and the start-up temperature of the fan (331) is defined as the third threshold, which is less than the second threshold.

9. The single-phase direct-cooling immersion liquid cooling control method as described in claim 8, characterized in that, When monitoring the temperature at the liquid outlet of the liquid cooling unit, the temperature values ​​at multiple points are measured within a certain period of time. The maximum values ​​among the multiple temperature values ​​are averaged to obtain the monitored value. The monitored value is then compared with the second threshold and the third threshold.

10. The single-phase direct-cooling immersion liquid cooling control method as described in claim 5, characterized in that, Monitor the internal temperature value of the server (6) and take the difference between the internal temperature value of the server (6) and the liquid outlet temperature value of the liquid cooling unit. Define the standard value of the difference as the fourth threshold. When the actual monitored difference is greater than the fourth threshold, increase the operating frequency of the cooling unit (3).

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