Heat dissipation system and control method

Abstract

The application discloses a heat dissipation system and a control method, relates to the technical field of air conditioners, and is used for a data machine room. A refrigerant circulation flow path and a water circulation flow path are formed on the heat dissipation system. A compressor, an outdoor heat exchanger, a throttling device and an indoor heat exchanger are sequentially arranged on the refrigerant circulation flow path. A heat exchanger is further arranged on the refrigerant circulation flow path. In the refrigerant flow direction, the heat exchanger is located at the rear side of the throttling device, so that the refrigerant passes through the heat exchanger first and then passes through the throttling device. The heat exchanger is formed with a first flow channel section and a second flow channel section which are mutually spaced and can exchange heat. The first flow channel section is located on the refrigerant circulation flow path. A pressurizing pump and a water cooling device are sequentially arranged on the water circulation flow path. The water cooling device is used for cooling water on the water circulation flow path. The second flow channel section is located on the water circulation flow path. The energy efficiency optimization brought by the complementation of the double cold sources is realized, the operation stability of the system under complex working conditions is enhanced, and the occurrence of high-pressure faults is prevented.

Description

Technical Field

[0001] This invention relates to the technical field of heat dissipation systems and control methods, and particularly to a heat dissipation system and control method. Background Technology

[0002] Precision air conditioners for data centers mainly adopt a single heat dissipation type, either pure air cooling or pure water cooling. Air-cooled precision air conditioners consist of an indoor unit, an outdoor condenser, and refrigerant piping. They achieve heat exchange in the data center through refrigerant gas-liquid phase change and outdoor air convection. They have a simple structure and flexible deployment. Water-cooled precision air conditioners consist of an indoor unit, a cooling tower, a circulating water pump, and water piping. They rely on water circulation for heat exchange and dissipation, and air cooling is limited to certain cooling scenarios.

[0003] Pure air-cooled air conditioners experience a sharp drop in heat dissipation efficiency in high-temperature summer environments, which can easily lead to compressor high-pressure protection shutdown, and the outdoor fan continuously runs at high speed, generating significant noise. Although pure water-cooled air conditioners have higher heat exchange efficiency, their system piping is complex. Once a single point of failure such as a water pump failure or pipe leakage occurs, it can easily lead to overall cooling failure, and their energy efficiency is lower under low-load conditions in winter. Summary of the Invention

[0004] The main objective of this invention is to propose a heat dissipation system and control method, which aims to achieve intelligent coordination and redundant backup of dual cooling modes, thereby improving the stability and overall energy efficiency of the system under complex operating conditions.

[0005] To achieve the above objectives, the present invention proposes a heat dissipation system for a data center, characterized in that a refrigerant circulation path and a water circulation path are formed in the heat dissipation system; A compressor, an outdoor heat exchanger, a throttling device, and an indoor heat exchanger are sequentially arranged in the refrigerant circulation path. A heat exchanger is also provided in the refrigerant circulation path. The heat exchanger is located behind the throttling device along the refrigerant flow direction, so that the refrigerant passes through the heat exchanger first and then through the throttling device. The heat exchanger has a first flow channel section and a second flow channel section that are spaced apart from each other and capable of heat exchange. The first flow channel section is located in the refrigerant circulation path. A booster pump and a water cooling device are sequentially installed on the water circulation path. The water cooling device is used to cool the water on the water circulation path. The second flow channel section is located on the water circulation path.

[0006] Preferably, the heat exchanger is located between the outdoor heat exchanger and the throttling device.

[0007] Preferably, the heat exchanger includes at least a shell-and-tube heat exchanger.

[0008] Preferably, a liquid storage tank is provided between the shell-and-tube heat exchanger and the throttling device.

[0009] Preferably, a drying filter is provided between the liquid storage tank and the throttling device; and / or, An electromagnetic valve is installed between the liquid storage tank and the throttling device.

[0010] Preferably, the throttling device includes an expansion valve disposed between the dryer filter and the indoor heat exchanger.

[0011] Preferably, the water cooling device includes at least a cooling tower, which has an inlet and an outlet, and the outlet is connected to the cooling water inlet of the second flow channel section of the heat exchanger via a pipeline; The pump body outlet of the booster pump is connected to the water inlet, and the pump body inlet of the booster pump is connected to the cooling water outlet of the second flow channel section of the heat exchanger.

[0012] Preferably, a silencer is provided in the refrigerant circulation path, and the silencer is located between the compressor and the outdoor heat exchanger.

[0013] Furthermore, to achieve the above objectives, the present invention also provides a control method, wherein a refrigerant circulation path and a water circulation path are formed on the heat dissipation system, and a compressor, an outdoor heat exchanger, a throttling device, and an indoor heat exchanger are sequentially arranged on the refrigerant circulation path. A heat exchanger is also provided on the refrigerant circulation path, flowing upward along the refrigerant. The heat exchanger is located behind the throttling device, such that the refrigerant passes through the heat exchanger first and then through the throttling device. The heat exchanger has a first flow channel section and a second flow channel section that are spaced apart from each other and capable of heat exchange. The first flow channel section is located on the refrigerant circulation path, and a booster pump and a water cooling device are sequentially arranged on the water circulation path. The water cooling device is used to cool the water on the water circulation path. The second flow channel section is located on the water circulation path. The heat dissipation system includes a first fan corresponding to the outdoor heat exchanger. The control method includes: Obtain outdoor ambient temperature parameters, thermal load parameters of equipment in the data center, and fault parameters of equipment on the water circulation path; When there is no fault in the equipment on the water circulation path, the first fan, the water pump and the cooling tower are selectively turned on according to the ambient temperature parameters and the heat load parameters, so that the refrigerant flowing into the throttling device can be cooled first through the outdoor heat exchanger and / or the water circulation path; When the equipment in the water circulation path malfunctions, the first fan is controlled to start working, and the water pump and the cooling tower stop working, so that the refrigerant flowing into the throttling device can only be cooled by passing through the outdoor heat exchanger first.

[0014] Preferably, when the equipment in the water circulation path is fault-free, the first fan, the water pump, and the cooling tower are selectively activated based on the ambient temperature parameters and the heat load parameters, including: When the ambient temperature parameter is higher than the preset high temperature threshold and the heat load parameter is higher than the preset high heat load threshold, the first fan is controlled to start working, the water pump and the cooling tower are started working, so that the refrigerant flowing into the throttling device can be cooled first through the outdoor heat exchanger and the water circulation path. When the ambient temperature parameter is within the preset temperature range and the heat load parameter is within the preset heat load range, the first fan is controlled to stop working, and the water pump and the cooling tower are started to work, so that the refrigerant flowing into the throttling device can only be cooled by passing through the water circulation path first. When the ambient temperature parameter is lower than the preset low temperature threshold, the first fan is controlled to start working, and the water pump and the cooling tower stop working, so that the refrigerant flowing into the throttling device can only be cooled by passing through the outdoor heat exchanger first.

[0015] In the technical solution provided by this invention, a compressor, an outdoor heat exchanger, a throttling device, and an indoor heat exchanger are sequentially arranged in the refrigerant circulation path. A heat exchanger is also provided in the refrigerant circulation path, located behind the throttling device along the refrigerant flow direction, so that the refrigerant passes through the heat exchanger first and then through the throttling device. The heat exchanger has a first flow channel section and a second flow channel section that are spaced apart from each other and capable of heat exchange. The first flow channel section is located in the refrigerant circulation path. A booster pump and a water cooling device are sequentially arranged in the water circulation path. The water cooling device is used to cool the water in the water circulation path. The second flow channel section is located in the water circulation path. This application not only realizes the energy efficiency optimization brought about by the complementary use of dual cold sources, but also enhances the operational stability of the system under complex operating conditions, effectively prevents the occurrence of high-pressure failures, and ensures the continuity and safety of the refrigeration cycle. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art 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 the structures shown in these drawings without creative effort.

[0017] Figure 1 A schematic diagram of an embodiment of the heat dissipation system provided by the present invention; Figure 2This is a flowchart illustrating the first embodiment of the control method provided by the present invention.

[0018] Explanation of icon numbers: 1. Compressor; 2. Outdoor heat exchanger; 3. Heat exchanger; 4. Throttling device; 5. Outdoor heat exchanger; 6. Silencer; 7. Booster pump; 8. Water cooling device.

[0019] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0022] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0023] This invention provides a heat dissipation system and control method. Figure 1 This is an embodiment of the heat dissipation system and control method provided by the present invention.

[0024] Please refer to the following: Figure 1The heat dissipation system is used in the data center and includes a refrigerant circulation path and a water circulation path. A compressor 1, an outdoor heat exchanger 2, a throttling device 4, and an indoor heat exchanger 5 are sequentially arranged on the refrigerant circulation path. A heat exchanger 3 is also provided on the refrigerant circulation path. The heat exchanger 3 is located behind the throttling device 4, so that the refrigerant passes through the heat exchanger 3 first and then the throttling device 4. A first flow channel section and a second flow channel section are formed within the heat exchanger 3, spaced apart and capable of heat exchange. The first flow channel section is located on the refrigerant circulation path. A booster pump 7 and a water cooling device 8 are sequentially arranged on the water circulation path. The water cooling device 8 is used to cool the water on the water circulation path. The second flow channel section is located on the water circulation path.

[0025] The refrigerant circulation path constitutes the main refrigeration circuit, responsible for transferring heat from inside the data center to the external environment. Common refrigerant circulation path types include direct expansion air cooling, direct expansion water cooling, heat pipe refrigerant circulation, and refrigerant pump circulation. In this application, the refrigerant circulation path is sequentially arranged with a compressor 1, an outdoor heat exchanger 2, a throttling device 4, a heat exchanger 3, and an outdoor heat exchanger 2. Heat from the data center is transferred to the refrigerant through the indoor heat exchanger 5, and the refrigerant is carried to the outdoor heat exchanger 2 and discharged into the atmosphere. The water circulation path serves as an auxiliary cooling circuit, providing additional cooling to the refrigerant through the exchange of sensible or latent heat of water. Cooling capacity replenishment requires a refrigerant phase change to generate low temperatures. The water system itself cannot provide cooling; it simply delivers the cooling capacity generated by the refrigerant to various parts of the computer room. The refrigerant circulation path and the water circulation path are two independent paths, but they are thermodynamically coupled through specific heat exchange nodes, thereby constructing a dual cooling system that combines air cooling and water cooling. Although this embodiment uses a data center as an application scenario, the architecture of this heat dissipation system is also applicable to other applications requiring high-reliability temperature control, such as energy storage power stations and industrial cooling equipment, and is not limited to the specific purpose of a data center.

[0026] This application, based on a paired compression refrigerant cycle, introduces an independent water cycle through a heat exchanger 3 to provide additional cooling for the high-pressure liquid refrigerant before throttling, ultimately improving the energy efficiency and cooling capacity of the refrigeration system. The booster pump 7 provides power for the water cycle, overcoming the resistance of the pipeline and heat exchanger, corresponding to the power role of "compressor 1" in the refrigerant cycle. The water cooling device 8 is the heat dissipation terminal of the water cycle, used to discharge the heat carried by the water to the outdoor environment, keeping the water at a low temperature, corresponding to the heat dissipation role of "outdoor radiator" in the refrigerant cycle. The water is cooled to a lower temperature by the water cooling device 8, becoming low-temperature chilled water. After being pressurized by the pump, it is delivered to the outer wall of the heat exchanger 3 or the outdoor heat exchanger 2, absorbing the heat of the refrigerant and increasing its own water temperature. The heated return water enters the water cooling device 8, dissipating the heat into the external environment through air cooling, evaporative cooling, etc., and the water temperature drops, completing the cycle. Common types of water cooling devices 8 include dry coolers, closed cooling towers, and those connected to the building cooling water system.

[0027] The first flow channel section belongs to the high-pressure side of the refrigerant circulation, carrying high-pressure liquid refrigerant. The second flow channel section belongs to the water circulation, carrying low-temperature circulating water. The two fluids are completely separated by the metal wall and do not come into contact with each other. Heat transfer is achieved only through heat conduction through the wall, which avoids cross-contamination between refrigerant and water and ensures heat exchange efficiency. The lower-temperature circulating water is used to perform secondary deep cooling on the liquid refrigerant condensed in the outdoor heat exchanger 2.

[0028] Heat exchangers are generally classified into indirect-flow heat exchangers, mixing heat exchangers, and regenerative heat exchangers. The circulating flow path heat exchanger of the present invention is more suitable as an indirect-flow heat exchanger. Indirect-flow heat exchangers are the most commonly used type of heat exchanger in industry. The hot and cold fluids are separated by a solid wall, so they do not come into contact with each other or mix. Heat is transferred through the solid wall. The heat is transferred from the hot fluid to one side of the wall by convection, and then to the other side of the wall by conduction through the solid wall. Finally, it is transferred to the cold fluid by convection, thus realizing heat transfer.

[0029] Therefore, in the technical solution provided by the present invention, a compressor 1, an outdoor heat exchanger 2, a throttling device 4, and an indoor heat exchanger 5 are sequentially arranged on the refrigerant circulation path. A heat exchanger 3 is also arranged on the refrigerant circulation path. Along the refrigerant flow direction, the heat exchanger 3 is located behind the throttling device 4, so that the refrigerant passes through the heat exchanger 3 first and then through the throttling device 4. The heat exchanger 3 has a first flow channel section and a second flow channel section that are spaced apart from each other and capable of heat exchange. The first flow channel section is located on the refrigerant circulation path. A booster pump 7 and a water cooling device 8 are sequentially arranged on the water circulation path. The water cooling device 8 is used to cool the water on the water circulation path. The second flow channel section is located on the water circulation path. This application not only realizes the energy efficiency optimization brought by the complementary dual cold sources, but also enhances the operational stability of the system under complex working conditions, effectively prevents the occurrence of high-pressure failures, and ensures the continuity and safety of the refrigeration cycle.

[0030] In order to maximize the use of the low-temperature cold source of the water circulation path to subcool the refrigerant that has already been partially condensed, thereby significantly increasing the enthalpy difference of refrigerant per unit mass without increasing the power consumption of compressor 1, and improving the system energy efficiency.

[0031] Specifically, in an embodiment of the present invention, the heat exchanger 3 is located between the outdoor heat exchanger 2 and the throttling device 4.

[0032] The refrigerant outlet of the outdoor heat exchanger 2 is connected to the inlet of the first flow channel section of the heat exchanger 3 via a pipeline, while the outlet of the first flow channel section of the heat exchanger 3 is connected to the inlet of the throttling device 4 via a pipeline. The aforementioned positional relationship ensures that after the refrigerant completes the air cooling heat dissipation in the outdoor environment, it can immediately enter the heat exchanger 3 for secondary cooling treatment. Compared with placing the heat exchanger 3 on the exhaust side of the compressor 1 or the indoor unit side, this application places the heat exchanger 3 between the condenser and the throttling device, which can avoid the direct impact of high-temperature and high-pressure gas on the water-side flow channel, thereby reducing the pressure requirements of the heat exchanger and improving the system safety factor. At the same time, it makes the refrigerant entering the throttling device 4 in a lower subcooling state, which is beneficial to improving the cooling capacity of the evaporator.

[0033] Heat exchanger 3 can also be installed before outdoor heat exchanger 2, which can reduce the inlet temperature of outdoor heat exchanger 2, thereby reducing the heat exchange load of outdoor heat exchanger 2 and improving the heat exchange efficiency of outdoor heat exchanger 2. This allows for pre-cooling before outdoor heat exchanger 2 cools down. However, if installed between outdoor heat exchangers 2, it needs to withstand high temperature and pressure, so the requirements for the temperature resistance, pressure resistance and sealing performance of heat exchanger 3 are extremely high, resulting in a significant increase in manufacturing cost. Heat exchanger 3 can also be installed after throttling device 4, which can regulate the two-phase state through heat exchange, so that the flash gas can be separated in advance or evenly distributed, improving the liquid distribution uniformity of each flow channel of indoor heat exchanger 5. However, the flow inside the pipe is a gas-liquid two-phase flow, the flow state is unstable, the heat transfer coefficient is low, and it is easy to have flow deviation, oscillation, and uncontrollable heat exchange effect. In addition, the fluid resistance after throttling by throttling device 4 will be lost, thereby reducing the inlet pressure of indoor heat exchanger 5, causing the evaporation temperature to drop, reducing the heat transfer temperature difference of indoor heat exchanger 5, and thus reducing the cooling efficiency.

[0034] Furthermore, the heat exchanger 3 includes at least a shell-and-tube heat exchanger.

[0035] Shell-and-tube heat exchangers are a classic industrial type of indirect heat exchanger and one of the most widely used heat exchange devices in data center refrigeration systems (chillers, water-cooled precision air conditioners, refrigerant subcooling systems). The core components consist of the shell, tube bundle, tube sheet, baffles, end caps, and inlet / outlet pipes. The shell is typically a cylindrical pressure vessel, mostly made of carbon steel or stainless steel, forming the flow space for the shell-side fluid, with tube sheets welded to both ends. The tube bundle consists of dozens to hundreds of heat exchange tubes (commonly used in refrigeration applications are internally threaded copper tubes or stainless steel tubes). The core wall of the heat exchanger has tubes inside which the fluid passes through. The tube sheet is located at both ends of the shell and is used to fix the heat exchange tubes while strictly separating the tube side and the shell side to prevent the two fluids from mixing. The baffles are installed inside the shell and are in the shape of an arc or a disc. They are used to support the tube bundle and guide the shell-side fluid to laterally scour the tube bundle, thereby enhancing turbulence and improving heat exchange efficiency. The end caps are installed outside the tube sheet and are used to distribute and collect the tube-side fluid. The internal baffles can be set to realize multi-pass flow and extend the fluid heat exchange path. The inlet and outlet pipes correspond to the fluid inlet and outlet interfaces of the shell side and the tube side, respectively.

[0036] In the first flow channel, high-pressure or medium-pressure liquid refrigerant flows from the outdoor heat exchanger 2 into the shell space, flushing the outer wall of the tube bundle and transferring heat to the water inside the tubes. The refrigerant itself is cooled to a subcooled liquid state and then flows to the throttling device 4. In the second flow channel, the pressurizing pump 7 drives low-temperature water into the tube bundle, where it absorbs heat from the shell-side refrigerant, raising its temperature. The water then flows out to the outdoor water-cooling device 8 for heat dissipation, completing the cycle. The two fluids are completely separated, preventing cross-contamination between refrigerant and water.

[0037] There are six types of indirect heat exchangers, including plate heat exchangers and shell-and-tube heat exchangers. Plate heat exchangers consist of multiple corrugated metal plates stacked and pressed together, forming narrow flow channels between the plates. Hot and cold fluids flow alternately through adjacent channels, relying on the thin plates for heat transfer. The heat exchange area can be easily adjusted by increasing or decreasing the number of plates; more plates result in a larger heat exchange area and higher heat exchange efficiency. However, plate heat exchangers have limited temperature and pressure resistance and are generally not suitable for high-pressure refrigerant subcooling scenarios. In the refrigerant circulation path of this invention, the refrigerant pressure is relatively high, so a shell-and-tube structure is preferred. In some other embodiments, shell-and-tube heat exchangers can also be used as a supplementary solution. A shell-and-tube heat exchanger consists of two tubes of different sizes concentrically nested together. One fluid flows through the inner tube, and another fluid flows through the annular gap; multiple sections are used in series. The inner tube can withstand extremely high pressure but cannot withstand large flow rates, making it more suitable for small refrigeration units, i.e., smaller computer rooms, and less suitable for the cooling needs of large computer rooms.

[0038] Furthermore, a liquid storage tank is provided between the shell-and-tube heat exchanger and the throttling device 4.

[0039] A liquid storage tank is connected in series on the pipeline between the outlet of the first flow channel section of heat exchanger 3 and the inlet of throttling device 4, forming an independent liquid refrigerant storage unit. While the shell-and-tube heat exchanger itself has a certain liquid storage capacity, in extreme conditions such as rapid switching between dual cooling modes, drastic fluctuations in heat load, or sudden changes in ambient temperature, the refrigerant migration within the system may exceed the volume adjustment range of the shell-and-tube heat exchanger. The added liquid storage tank provides additional liquid refrigerant storage space and a gas-liquid separation interface. For example, when the system switches from pure air-cooling mode to dual-cooling synergistic mode, the activation of the water-cooling circuit causes a rapid drop in condensing pressure, resulting in a large amount of refrigerant liquefying and flowing towards the front end of throttling device 4. The liquid storage tank can promptly accommodate this excess liquid refrigerant, preventing it from flooding the heat exchange surface of heat exchanger 3 or causing liquid slugging in throttling device 4. Conversely, when a sudden increase in load leads to a surge in evaporation, the liquid storage tank can promptly replenish the liquid refrigerant, maintaining a stable liquid supply.

[0040] Furthermore, a drying filter is provided between the liquid storage tank and the throttling device 4.

[0041] The dryer filter is connected in series in the refrigerant circulation path. Its interior is filled with adsorbents such as molecular sieves and filter screens. It is mainly used to remove residual moisture, metal shavings and other solid impurities in the refrigerant. During the operation of the dual cooling system, due to the frequent switching between air cooling and water cooling modes and the drastic changes in ambient temperature and humidity, trace amounts of moisture or wear particles are easily generated in the pipeline. If not removed in time, the moisture may freeze and cause ice blockage when flowing through the low-temperature throttling part, and the impurities may jam the valve core or wear the moving parts of the compressor. The installation of the dryer filter ensures the cleanliness and dryness of the refrigerant circuit from a physical perspective, which significantly improves the long-term operational reliability of the system under complex operating conditions.

[0042] An electromagnetic valve is provided between the liquid storage tank and the throttling device 4.

[0043] The solenoid valve can quickly open or close the refrigerant passage according to the needs of the system operation mode. For example, when the system detects a water circulation equipment failure and needs to switch to a pure air-cooled redundant mode, or during shutdown maintenance, the solenoid valve can quickly cut off the refrigerant flowing to the throttling device 4 to prevent abnormal migration of the refrigerant or accumulation on the low-pressure side during non-working periods.

[0044] Furthermore, the throttling device 4 includes an expansion valve disposed between the dryer filter and the indoor heat exchanger 5.

[0045] Refrigerant has a high boiling point under high pressure and cannot evaporate and absorb heat at room temperature. The expansion valve throttles the high-pressure liquid refrigerant through a narrow valve orifice, achieving a sudden pressure drop. The inlet of the expansion valve is high-pressure, medium-temperature, subcooled liquid refrigerant, and the outlet is low-temperature, low-pressure, gas-liquid two-phase refrigerant. By utilizing the characteristic that the boiling point of refrigerant decreases as the pressure decreases, the low-pressure refrigerant can boil and evaporate at a temperature lower than that of the air in the computer room, thereby absorbing heat from the computer room and achieving the purpose of cooling.

[0046] The high-pressure liquid refrigerant condensed in outdoor heat exchanger 2 directly enters the first flow channel section of shell-and-tube heat exchanger 3, where it is further cooled by the low-temperature water on the water circulation side, achieving a higher degree of subcooling. This highly subcooled liquid refrigerant then enters the expansion valve, where its pressure drops sharply after throttling, transforming into a low-temperature, low-pressure gas-liquid two-phase system. Due to the high subcooling before throttling, the proportion of flash gas generated during the throttling process is significantly reduced, resulting in a higher proportion of liquid refrigerant. The two-phase refrigerant then enters indoor heat exchanger 5, where it absorbs heat from the server room air and completely evaporates into a gaseous state. The expansion valve senses the superheat at the outlet of indoor heat exchanger 5 in real time and dynamically adjusts its opening to match server load fluctuations. The high subcooling also allows for a wider effective adjustment range for the expansion valve, ensuring sufficient cooling output even under extreme high-temperature conditions.

[0047] The water circulation path continuously provides low-temperature cooling water to the heat exchanger 3 through evaporative cooling, which is a key guarantee for achieving secondary deep cooling of the refrigerant. Specifically, in the embodiments of the present invention, the water cooling device 8 includes at least a cooling tower, which has an inlet and an outlet. The outlet is connected to the cooling water inlet of the second flow channel section of the heat exchanger 3 through a pipeline. The pump body outlet of the booster pump 7 is connected to the inlet, and the pump body inlet of the booster pump 7 is connected to the cooling water outlet of the second flow channel section of the heat exchanger 3.

[0048] The pressurized pump 7 delivers the heated cooling water from the outlet of the second flow channel section of the heat exchanger 3 to the inlet of the cooling tower. Inside the cooling tower, the cooling water exchanges heat and moisture with the outdoor air through spraying, packing contact, etc., and uses the latent heat of vaporization of water to remove heat, so that the water temperature drops and flows out from the outlet. It is then reinjected into the inlet of the second flow channel section of the heat exchanger 3 through the pipeline, thereby completing a complete cooling cycle. Although this embodiment uses a cooling tower as the specific implementation of the water cooling device 8, in other embodiments, the water cooling device 8 can also be a dry cooler, an evaporative condenser, or a chiller unit, etc., which can cool the circulating water, as long as it can maintain the low temperature of the cooling water in the water circulation path to meet the heat exchange requirements. This application does not limit it to a single type.

[0049] Because water has a much higher specific heat capacity than air, and its evaporative cooling process can approach the ambient wet-bulb temperature, the water circulation path can provide a more stable and lower-grade cold source under high-temperature conditions in summer compared to relying solely on air cooling from the outdoor heat exchanger 2. When the low-temperature cooling water flows through the second flow channel of the heat exchanger 3, it undergoes efficient counter-current or cross-flow heat exchange with the refrigerant from the outdoor heat exchanger 2 in the first flow channel, significantly reducing the refrigerant temperature and increasing the subcooling. The additional cooling capacity provided by the water circulation path not only directly increases the enthalpy difference per unit mass of refrigerant and improves the system's energy efficiency ratio, but more importantly, it enables the heat exchanger 3 to operate as a stable subcooler, avoiding the problem of refrigerant instability caused by ambient temperature fluctuations.

[0050] When the fan of outdoor heat exchanger 2 fails, the air inlet is blocked, or the ambient temperature rises extremely, causing a severe reduction in air-cooling capacity, the water circulation path can still operate independently to continue providing cooling capacity to heat exchanger 3, preventing the system from shutting down due to high-pressure protection. Conversely, during winter low temperatures or water circulation equipment maintenance, the system can seamlessly switch to pure air-cooling mode, relying solely on outdoor heat exchanger 2 for heat dissipation. This dual-cold-source backup design enhances the survivability and operational continuity of the heat dissipation system under complex environments and sudden failures, solving the shortcomings of traditional single cooling methods. Furthermore, the booster pump 7, cooling tower, and connecting pipes are all configured as independent modules, facilitating flexible selection and layout optimization based on the actual heat load and installation conditions of the computer room.

[0051] In another embodiment of the present invention, a silencer 6 is provided in the refrigerant circulation path, and the silencer 6 is located between the compressor 1 and the outdoor heat exchanger 2.

[0052] When the compressor 1 is working, it will generate periodic exhaust pulsations and high-speed airflow noise. If these noises are directly transmitted to the subsequent pipelines and outdoor heat exchanger 2, they are very likely to cause pipeline resonance and be radiated outwards through the fan, causing serious environmental noise pollution. The silencer 6 can use its internal expansion chamber, perforated pipe or sound-absorbing material to reflect, interfere or absorb the noise at the source stage of the noise propagation, thereby greatly reducing the energy of exhaust pulse vibration and high-frequency airflow noise. The silencer 6 can also be a resistive silencer 6, an impedance composite silencer 6 or an active silencer 6, as long as it can attenuate the airflow noise in the refrigerant pipeline.

[0053] Furthermore, the present invention proposes a control method in which a refrigerant circulation path and a water circulation path are formed on the heat dissipation system. A compressor, an outdoor heat exchanger, a throttling device, and an indoor heat exchanger are sequentially arranged on the refrigerant circulation path. A heat exchanger is also provided on the refrigerant circulation path, flowing upward along the refrigerant. The heat exchanger is located behind the throttling device, so that the refrigerant passes through the heat exchanger first and then through the throttling device. The heat exchanger has a first flow channel section and a second flow channel section that are spaced apart from each other and capable of heat exchange. The first flow channel section is located on the refrigerant circulation path. A booster pump and a water cooling device are sequentially arranged on the water circulation path. The water cooling device is used to cool the water on the water circulation path. The second flow channel section is located on the water circulation path. The heat dissipation system includes a first fan corresponding to the outdoor heat exchanger.

[0054] Reference Figure 2 , Figure 2 This is a flowchart illustrating the first embodiment of a smartwatch control method according to the present invention.

[0055] In this embodiment, the control method includes the following steps: Step S10: Obtain outdoor ambient temperature parameters, thermal load parameters of equipment in the data center, and fault parameters of equipment on the water circulation path; It should be noted that the ambient temperature parameter reflects the quality of the external natural cold source and the potential of air cooling, and can be collected in real time by temperature sensors installed at the outdoor unit's air inlet or in the external environment. The heat load parameter characterizes the current heat generation intensity and cooling demand inside the data center, and can be obtained indirectly or directly by monitoring return air temperature, server power consumption statistics, or flow meter readings. The fault parameters cover the operating status feedback of key components in the water circulation path (such as booster pumps, water cooling devices and their associated valves, sensors, etc.), including but not limited to signals such as motor overload, abnormal flow, pressure exceeding limits, communication loss, or mechanical jamming.

[0056] Step S20: When there is no fault in the equipment on the water circulation path, the first fan, the water pump and the cooling tower are selectively turned on according to the ambient temperature parameter and the heat load parameter, so that the refrigerant flowing into the throttling device can be cooled first through the outdoor heat exchanger and / or the water circulation path. It should be noted that when the system determines that the water circulation path is in a healthy and usable state, the control logic enters a multi-objective optimization mode. The system no longer mechanically maintains a single operating state, but instead uses ambient temperature and heat load as joint variables to dynamically find the best cooling combination.

[0057] In practice, during the high-temperature and high-load period in summer, the first fan, booster pump, and water cooling device can be turned on simultaneously to maximize heat dissipation capacity by utilizing the synergy of the two cold sources and prevent high-pressure failures. During the transitional season or medium-load period, the high efficiency of water cooling can be prioritized, and the first fan can be turned off to reduce noise and fan energy consumption. During the low-temperature and low-load period in winter, outdoor natural cold sources can be fully utilized, and only the first fan can be turned on while the water circuit equipment is shut down to avoid the risk of water circuit freezing and reduce water pump power consumption.

[0058] Furthermore, to improve the overall performance of the cooling system under different seasons and workloads throughout the year, this application specifically divides the selective start-up strategy for equipment on the water circulation path when there are no faults into three typical operating modes, including: When the ambient temperature parameter is higher than the preset high temperature threshold and the heat load parameter is higher than the preset high heat load threshold, the first fan is controlled to start working, the water pump and the cooling tower are started working, so that the refrigerant flowing into the throttling device can be cooled first through the outdoor heat exchanger and the water circulation path. When the ambient temperature parameter is within the preset temperature range and the heat load parameter is within the preset heat load range, the first fan is controlled to stop working, and the water pump and the cooling tower are started to work, so that the refrigerant flowing into the throttling device can only be cooled by passing through the water circulation path first. When the ambient temperature parameter is lower than the preset low temperature threshold, the first fan is controlled to start working, and the water pump and the cooling tower stop working, so that the refrigerant flowing into the throttling device can only be cooled by passing through the outdoor heat exchanger first.

[0059] In practice, relying solely on the outdoor heat exchanger for air cooling will cause the condensing temperature to rise sharply due to the excessively high ambient dry-bulb temperature. This not only leads to a significant increase in compressor power consumption but also easily triggers high-pressure protection shutdown. By simultaneously activating the booster pump and water cooling device, the low-temperature chilled water generated by evaporative cooling is used to deeply pre-cool the refrigerant in the heat exchanger, which can significantly reduce the enthalpy of the refrigerant entering the outdoor heat exchanger, thereby effectively suppressing the rise in exhaust pressure. At the same time, the continuous operation of the first fan provides additional heat dissipation redundancy for the system, ensuring that the system can still maintain sufficient subcooling and cooling capacity output even in hot and humid weather with high wet-bulb temperatures.

[0060] The pure water cooling mode is suitable for normal operating conditions with moderate ambient temperature and stable data center load, such as during transitional seasons or at night. Actively shutting down the primary fan completely eliminates the aerodynamic noise generated by the high-speed operation of the outdoor fan, significantly improving the acoustic environment around the data center and resolving noise pollution issues. Furthermore, it avoids ineffective energy consumption by the fan motor, allowing the system to operate in a higher energy efficiency ratio range.

[0061] In low-temperature environments, outdoor air itself is a high-quality natural cold source. Outdoor heat exchangers only need a low fan speed to meet heat dissipation requirements, without the need to start the water circulation system. The operation of the booster pump and water cooling device is forcibly stopped. The primary purpose is to prevent the cooling water pipes from freezing and cracking at low temperatures, thus avoiding equipment damage and leakage risks. Secondly, it avoids the energy consumption of water pumps and cooling tower fans running idle when water cooling is not required, and eliminates the problem of unstable liquid supply from the throttling device caused by low condensing pressure due to low water temperature.

[0062] Step S30: When the equipment in the water circulation path malfunctions, the first fan is controlled to start working, and the water pump and the cooling tower stop working, so that the refrigerant flowing into the throttling device can only be cooled by passing through the outdoor heat exchanger first.

[0063] It should be noted that in fault mode, the system can also issue maintenance alarm signals simultaneously to prompt maintenance personnel to carry out timely repairs, but will always maintain a minimum cooling output until the repair is completed to ensure that the core equipment in the computer room does not crash due to overheating.

[0064] In practice, if any critical equipment malfunctions in the water circulation path (such as a damaged booster pump, a blocked water cooling device, or a leaking pipeline), the control system immediately triggers a fault-safe response, unconditionally cutting off the water-side power source (stopping the booster pump and water cooling device), and simultaneously forcibly starting the first fan, allowing the system to seamlessly switch to pure air-cooled operation mode. At this time, the refrigerant circulation path is not interrupted, and the high-temperature, high-pressure refrigerant can still flow through the outdoor heat exchanger to release heat to the ambient air. Although the heat dissipation efficiency may be lower than that in the water-cooled mode under high-temperature conditions, it is sufficient to maintain the basic refrigeration cycle, avoiding the catastrophic consequences of the entire refrigeration system being paralyzed due to a single point of failure in the water system.

[0065] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A heat dissipation system for a data center, characterized in that, The heat dissipation system has a refrigerant circulation path and a water circulation path. A compressor, an outdoor heat exchanger, a throttling device, and an indoor heat exchanger are sequentially arranged in the refrigerant circulation path. A heat exchanger is also provided in the refrigerant circulation path. The heat exchanger is located behind the throttling device along the refrigerant flow direction, so that the refrigerant passes through the heat exchanger first and then through the throttling device. The heat exchanger has a first flow channel section and a second flow channel section that are spaced apart from each other and capable of heat exchange. The first flow channel section is located in the refrigerant circulation path. A booster pump and a water cooling device are sequentially installed on the water circulation path. The water cooling device is used to cool the water on the water circulation path. The second flow channel section is located on the water circulation path.

2. The heat dissipation system as described in claim 1, characterized in that, The heat exchanger is located between the outdoor heat exchanger and the throttling device.

3. The heat dissipation system as described in claim 1, characterized in that, The heat exchanger includes at least a shell-and-tube heat exchanger.

4. The heat dissipation system as described in claim 3, characterized in that, A liquid storage tank is provided between the shell-and-tube heat exchanger and the throttling device.

5. The heat dissipation system as described in claim 4, characterized in that, A drying filter is provided between the liquid storage tank and the throttling device; and / or, An electromagnetic valve is installed between the liquid storage tank and the throttling device.

6. The heat dissipation system as described in claim 5, characterized in that, The throttling device includes an expansion valve disposed between the dryer filter and the indoor heat exchanger.

7. The heat dissipation system as described in claim 1, characterized in that, The water cooling device includes at least a cooling tower, which has an inlet and an outlet, and the outlet is connected to the cooling water inlet of the second flow channel section of the heat exchanger via a pipeline. The pump body outlet of the booster pump is connected to the water inlet, and the pump body inlet of the booster pump is connected to the cooling water outlet of the second flow channel section of the heat exchanger.

8. The heat dissipation system as described in claim 1, characterized in that, A silencer is provided in the refrigerant circulation path, and the silencer is located between the compressor and the outdoor heat exchanger.

9. A control method based on a heat dissipation system as described in any one of claims 1 to 8, said heat dissipation system comprising a first fan disposed corresponding to the outdoor heat exchanger, characterized in that, The control method includes: Obtain outdoor ambient temperature parameters, thermal load parameters of equipment in the data center, and fault parameters of equipment on the water circulation path; When there is no fault in the equipment on the water circulation path, the first fan, the water pump and the cooling tower are selectively turned on according to the ambient temperature parameters and the heat load parameters, so that the refrigerant flowing into the throttling device can be cooled first through the outdoor heat exchanger and / or the water circulation path; When the equipment in the water circulation path malfunctions, the first fan is controlled to start working, and the water pump and the cooling tower stop working, so that the refrigerant flowing into the throttling device can only be cooled by passing through the outdoor heat exchanger first.

10. The control method as described in claim 9, characterized in that, When the equipment in the water circulation path is fault-free, the first fan, the water pump, and the cooling tower are selectively activated based on the ambient temperature parameters and the heat load parameters, including: When the ambient temperature parameter is higher than the preset high temperature threshold and the heat load parameter is higher than the preset high heat load threshold, the first fan is controlled to start working, the water pump and the cooling tower are started working, so that the refrigerant flowing into the throttling device can be cooled first through the outdoor heat exchanger and the water circulation path. When the ambient temperature parameter is within the preset temperature range and the heat load parameter is within the preset heat load range, the first fan is controlled to stop working, and the water pump and the cooling tower are started to work, so that the refrigerant flowing into the throttling device can only be cooled by passing through the water circulation path first. When the ambient temperature parameter is lower than the preset low temperature threshold, the first fan is controlled to start working, and the water pump and the cooling tower stop working, so that the refrigerant flowing into the throttling device can only be cooled by passing through the outdoor heat exchanger first.

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