Heat management method based on waste heat utilization of computing power center and liquid hydrogen storage and transportation cold energy management

Abstract

The present application relates to an energy thermal management method based on computing power center waste heat utilization and liquid hydrogen storage and transportation cold energy management. The method transmits the liquid cooling heat dissipation waste heat of the computing power center to the heat carrier fluid circuit through the heat exchanger unit for driving the liquid hydrogen gasification and temperature rise; according to the liquid hydrogen supply flow, the storage tank state, the heat carrier fluid temperature and the hydrogen outlet temperature, the heat carrier fluid flow is dynamically adjusted, so that the input heat power matches the total enthalpy change required by the liquid hydrogen gasification. The cold energy recovery heat exchanger is arranged downstream of the gasifier, the cold energy released by the hydrogen temperature rise is captured, and the excess cold energy is preferentially supplied to the hydrogenation machine precooler through the heat carrier circuit, and the excess cold energy is used for the liquid hydrogen storage tank cold preservation. The system also sets the heat storage device to suppress the computing power center waste heat fluctuation, realizes the collaborative closed loop management of waste heat utilization, liquid hydrogen gasification, cold energy recovery and storage tank cold preservation, reduces the gasification power consumption and liquid hydrogen evaporation loss.

Description

Technical Field

[0001] This invention belongs to the technical fields of hydrogen energy storage and transportation, waste heat recovery from computing centers, and integrated energy thermal management, specifically relating to a thermal management method based on waste heat utilization from computing centers and cold energy management of liquid hydrogen storage and transportation. Background Technology

[0002] Liquid hydrogen typically needs to be stored and transported under cryogenic conditions of approximately 20K. Due to the extreme temperature difference between liquid hydrogen and the external environment, even with a vacuum multilayer insulation structure, heat leakage is unavoidable, causing the liquid hydrogen to continuously evaporate and form vapor gas, increasing the risk of overpressure in the storage tank and hydrogen loss.

[0003] On the other hand, liquid hydrogen needs to be vaporized and heated before being supplied to hydrogen refueling machines or downstream hydrogen-using equipment. Existing air-bath vaporizers are significantly affected by ambient temperature, and their vaporization capacity is insufficient under cold or high-load conditions; while electrically heated vaporization methods consume a large amount of electrical energy, reducing the economic efficiency of liquid hydrogen storage, transportation and refueling systems.

[0004] Meanwhile, computing centers, especially AI computing centers, continuously generate a large amount of medium- and low-temperature waste heat during operation. This waste heat is usually discharged into the environment through cooling towers, dry coolers, or liquid cooling systems, failing to be effectively utilized. In existing technologies, there is a lack of coordinated control mechanisms between the waste heat from computing centers and the heat used for liquid hydrogen vaporization, the recovery of liquid hydrogen cold energy, and the cold storage of storage tanks, resulting in the coexistence of waste heat at the hot end and cold energy at the cold end. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, this invention provides a method for suppressing liquid hydrogen storage evaporation and connecting cold energy pipes based on the thermal conductivity of artificial diamond. The objective of this invention can be achieved through the following technical solution: Thermal management methods based on waste heat utilization from computing centers and cold energy management for liquid hydrogen storage and transportation include: S1: Obtain the waste heat generated by the liquid cooling heat dissipation circuit of the computing center, transfer the waste heat to the heat transfer fluid circuit through the heat exchanger group, and send the heat transfer fluid into the hot side flow channel of the liquid hydrogen vaporizer. S2: The liquid hydrogen output from the liquid hydrogen storage tank is sent into the cold side flow channel of the liquid hydrogen vaporizer, so that the heat transfer fluid and the liquid hydrogen exchange heat in the liquid hydrogen vaporizer, and the waste heat of the computing center is used to provide the heat required for vaporization and heating of the liquid hydrogen. S3: Real-time acquisition of liquid hydrogen supply flow rate, liquid hydrogen storage tank pressure, liquid hydrogen storage tank level, heat transfer fluid inlet temperature, and vaporized hydrogen outlet temperature; and adjustment of heat transfer fluid flow rate or heat transfer fluid pump speed based on the total enthalpy change required for liquid hydrogen to rise from the storage tank temperature, vaporize, and reach the target supply temperature, so that the heat power input to the liquid hydrogen vaporizer matches the heat power required for liquid hydrogen vaporization and heating. S4: A cold energy recovery heat exchanger is installed downstream of the liquid hydrogen vaporizer to capture the cold energy released during the heating process of hydrogen from the cryogenic temperature and transfer the cold energy to the refrigerant circuit. S5: Selectively deliver the cooling capacity in the refrigerant circuit to at least one of the following via the cold energy distribution pipeline: the hydrogen dispenser precooler, the liquid hydrogen storage tank insulation branch, and the bypass cooling branch; wherein, when the hydrogen dispenser is in the refueling state, the cooling capacity is preferentially delivered to the hydrogen dispenser precooler; when the hydrogen dispenser is not in the refueling state, at least a portion of the cooling capacity is delivered to the liquid hydrogen storage tank insulation branch to suppress the evaporation of liquid hydrogen in the liquid hydrogen storage tank; S6: When the waste heat power of the computing center is higher than the heat power required for liquid hydrogen vaporization and heating, the excess heat is stored in the heat storage device; when the waste heat power of the computing center is lower than the heat power required for liquid hydrogen vaporization and heating or when the system is started, the heat storage device replenishes heat to the heat transfer fluid circuit, thereby forming an energy thermal management closed loop of computing center waste heat utilization, liquid hydrogen vaporization heating, hydrogen cold energy recovery, and liquid hydrogen storage and transportation cold energy reuse.

[0006] Specifically, the liquid cooling circuit of the computing center is a microchannel liquid cooling circuit of the AI ​​intelligent computing chip cluster, and the heat carrier fluid is water, ethylene glycol aqueous solution, fluorinated liquid or insulating coolant. The heat carrier fluid circulates between the heat exchange unit and the liquid hydrogen vaporizer through a variable frequency magnetic drive pump.

[0007] Specifically, the hot-side flow channel and the cold-side flow channel of the liquid hydrogen vaporizer are arranged in a counter-current manner, and the flow direction of the heat transfer fluid is opposite to that of the liquid hydrogen.

[0008] Specifically, the heat transfer wall of the liquid hydrogen vaporizer includes a high thermal conductivity layer and metal encapsulation layers located on both sides of the high thermal conductivity layer. The surface of the hot-side metal encapsulation layer is provided with a micro-rib array that contacts the heat transfer fluid, and the surface of the cold-side metal encapsulation layer is provided with a microchannel array that contacts the liquid hydrogen.

[0009] Specifically, the total enthalpy change includes the sensible heat of liquid hydrogen as it rises from the tank temperature to the saturation temperature, the latent heat of vaporization required for liquid hydrogen to change from liquid to gas, and the sensible heat of gas required for gaseous hydrogen to continue to rise to the target supply temperature.

[0010] Specifically, the adjustment of the heat transfer fluid flow rate or the heat transfer fluid pump speed includes: calculating the target thermal power based on the liquid hydrogen supply flow rate and the total enthalpy change; calculating the actual input thermal power based on the heat transfer fluid inlet temperature and the heat transfer fluid outlet temperature; and using the deviation between the vaporized hydrogen outlet temperature and the target supply temperature as feedback quantity to perform closed-loop control of the heat transfer fluid regulating valve opening or the heat transfer fluid pump speed.

[0011] Specifically, the cold energy recovery heat exchanger is a plate heat exchanger, a coiled tube heat exchanger, or a printed circuit board heat exchanger. The cold energy recovery heat exchanger includes a hydrogen side channel and a refrigerant side channel, and non-contact heat exchange is performed between the hydrogen side channel and the refrigerant side channel.

[0012] Specifically, the refrigerant in the refrigerant circuit is one or more of silicone oil, ethylene glycol aqueous solution, fluorinated liquid, liquid nitrogen, or cryogenic helium. The refrigerant is cooled by the cold energy recovery heat exchanger before entering the cold energy distribution pipeline. The hot-side flow channel and cold-side flow channel of the liquid hydrogen vaporizer and / or the hydrogen-side flow channel and refrigerant-side flow channel of the cold energy recovery heat exchanger are composed of high-flux tubes. The high-flux tubes include a pressure-bearing tube body and a metal-reinforced heat exchange layer disposed on the inner wall and / or outer wall of the pressure-bearing tube body. The metal-reinforced heat exchange layer is used to increase the effective heat exchange area to enhance the vaporization and boiling heat exchange of liquid hydrogen and the cryogenic convection heat exchange of hydrogen, heat transfer fluid, or refrigerant.

[0013] Specifically, the cold energy distribution pipeline includes a precooler branch, a liquid hydrogen storage tank insulation branch, and a bypass cooling branch; the precooler branch connects the cold energy recovery heat exchanger to the hydrogen dispenser precooler, the liquid hydrogen storage tank insulation branch connects the cold energy recovery heat exchanger to the liquid hydrogen storage tank insulation heat exchange unit, and the bypass cooling branch connects the cold energy recovery heat exchanger to the dry cooler or the ambient heat dissipation unit.

[0014] Specifically, the precooler branch, the liquid hydrogen storage tank insulation branch, and the bypass cooling branch distribute cooling capacity through a three-way proportional regulating valve, a solenoid switch valve, or a combination thereof. When the hydrogen dispenser is in the refueling state, the precooler branch is opened and cooling capacity is distributed preferentially. When the hydrogen dispenser is not in the refueling state and the refrigerant outlet temperature is lower than a preset threshold, the liquid hydrogen storage tank insulation branch is opened. When the refrigerant circuit pressure exceeds the safety threshold or all cooling branches do not meet the opening conditions, the bypass cooling branch is opened.

[0015] Specifically, the heat storage device is connected in parallel or in series on the main heat-carrying fluid pipeline between the heat exchanger unit and the liquid hydrogen vaporizer. The heat storage device is a phase change heat storage device, a water heat storage device, a molten salt heat storage device, or a solid sensible heat storage device.

[0016] Specifically, the energy thermal management method is executed by a PLC controller or an industrial control computer. The PLC controller or industrial control computer coordinates and controls the working status of the heat transfer fluid pump, heat transfer fluid regulating valve, heat storage device switching valve, refrigerant circulation pump, and cold energy distribution valve based on the load signal of the computing center chip, the liquid hydrogen supply demand signal, the liquid hydrogen storage tank status signal, the hydrogen outlet temperature signal, the heat transfer fluid temperature signal, the refrigerant temperature signal, and the loop pressure signal.

[0017] The beneficial effects of this invention are as follows: This invention uses sintered high-throughput tube bundles as the core enhanced heat exchange structure of the liquid hydrogen vaporizer and / or cold energy recovery heat exchanger. This allows the low-to-medium temperature waste heat continuously generated by the computing center to be stably transferred to liquid hydrogen with a small heat exchange temperature difference, reducing or avoiding energy consumption for electrically heated vaporization. The high-throughput tubes also enhance low-temperature convective heat exchange of hydrogen, heat transfer fluid, or refrigerant, improving the efficiency of hydrogen cold energy recovery, and using the recovered cold energy for hydrogen pre-cooling and liquid hydrogen storage tank insulation. Through heat storage devices and closed-loop control, it can adapt to fluctuations in computing load, hydrogen supply flow rate, and system start-up and shutdown conditions, improving the stability and overall energy efficiency of the liquid hydrogen storage, transportation, and refueling system. This invention can adapt to fluctuations in computing load, changes in liquid hydrogen supply flow rate, and hydrogen supply load, while reducing the volume and heat exchange area requirements of the heat exchanger and improving the coupling efficiency of waste heat utilization, liquid hydrogen vaporization, cold energy recovery, and storage tank insulation. Attached Figure Description

[0018] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0019] Figure 1 This is a schematic flowchart of the energy thermal management method of the present invention; Figure 2 This is a schematic diagram of the control logic for waste heat recovery, liquid hydrogen vaporization, and cold energy distribution in the computing center of this invention. Detailed Implementation

[0020] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this disclosure more comprehensive and complete, and to fully convey the concept of example embodiments to those skilled in the art. Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a full understanding of embodiments of this disclosure. However, those skilled in the art will recognize that the technical solutions of this disclosure can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring aspects of this disclosure. The blocks shown in the drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices. The flowcharts shown in the drawings are merely illustrative and do not necessarily include all contents and operations / steps, nor do they necessarily have to be performed in the order described. For example, some operations / steps can be broken down, while others can be combined or partially combined. Therefore, the actual execution order may change depending on the actual situation.

[0021] To further illustrate the technical means and effects adopted by the present invention in order to achieve the intended purpose, the following detailed description is provided in conjunction with the accompanying drawings and preferred embodiments, based on the specific implementation methods, structures, features and effects of the present invention.

[0022] Please see Figures 1-2 Thermal management methods based on waste heat utilization in computing centers and cold energy management for liquid hydrogen storage and transportation include: S1: Obtain the waste heat generated by the liquid cooling heat dissipation circuit of the computing center, transfer the waste heat to the heat transfer fluid circuit through the heat exchanger group, and send the heat transfer fluid into the hot side flow channel of the liquid hydrogen vaporizer. S2: The liquid hydrogen output from the liquid hydrogen storage tank is sent into the cold side flow channel of the liquid hydrogen vaporizer, so that the heat transfer fluid and the liquid hydrogen exchange heat in the liquid hydrogen vaporizer, and the waste heat of the computing center is used to provide the heat required for vaporization and heating of the liquid hydrogen. S3: Real-time acquisition of liquid hydrogen supply flow rate, liquid hydrogen storage tank pressure, liquid hydrogen storage tank level, heat transfer fluid inlet temperature, and vaporized hydrogen outlet temperature; and adjustment of heat transfer fluid flow rate or heat transfer fluid pump speed based on the total enthalpy change required for liquid hydrogen to rise from the storage tank temperature, vaporize, and reach the target supply temperature, so that the heat power input to the liquid hydrogen vaporizer matches the heat power required for liquid hydrogen vaporization and heating. S4: A cold energy recovery heat exchanger is installed downstream of the liquid hydrogen vaporizer to capture the cold energy released during the heating process of hydrogen from the cryogenic temperature and transfer the cold energy to the refrigerant circuit. S5: Selectively deliver the cooling capacity in the refrigerant circuit to at least one of the following via the cold energy distribution pipeline: the hydrogen dispenser precooler, the liquid hydrogen storage tank insulation branch, and the bypass cooling branch; wherein, when the hydrogen dispenser is in the refueling state, the cooling capacity is preferentially delivered to the hydrogen dispenser precooler; when the hydrogen dispenser is not in the refueling state, at least a portion of the cooling capacity is delivered to the liquid hydrogen storage tank insulation branch to suppress the evaporation of liquid hydrogen in the liquid hydrogen storage tank; S6: When the waste heat power of the computing center is higher than the heat power required for liquid hydrogen vaporization and heating, the excess heat is stored in the heat storage device; when the waste heat power of the computing center is lower than the heat power required for liquid hydrogen vaporization and heating or when the system is started, the heat storage device replenishes heat to the heat transfer fluid circuit, thereby forming an energy thermal management closed loop of computing center waste heat utilization, liquid hydrogen vaporization heating, hydrogen cold energy recovery, and liquid hydrogen storage and transportation cold energy reuse.

[0023] Specifically, the liquid cooling circuit of the computing center is a microchannel liquid cooling circuit of the AI ​​intelligent computing chip cluster, and the heat carrier fluid is water, ethylene glycol aqueous solution, fluorinated liquid or insulating coolant. The heat carrier fluid circulates between the heat exchange unit and the liquid hydrogen vaporizer through a variable frequency magnetic drive pump.

[0024] Specifically, the hot-side flow channel and the cold-side flow channel of the liquid hydrogen vaporizer are arranged in a counter-current manner, and the flow direction of the heat transfer fluid is opposite to that of the liquid hydrogen.

[0025] Specifically, the heat transfer wall of the liquid hydrogen vaporizer includes a high thermal conductivity layer and metal encapsulation layers located on both sides of the high thermal conductivity layer. The surface of the hot-side metal encapsulation layer is provided with a micro-rib array that contacts the heat transfer fluid, and the surface of the cold-side metal encapsulation layer is provided with a microchannel array that contacts the liquid hydrogen.

[0026] Specifically, the total enthalpy change includes the sensible heat of liquid hydrogen as it rises from the tank temperature to the saturation temperature, the latent heat of vaporization required for liquid hydrogen to change from liquid to gas, and the sensible heat of gas required for gaseous hydrogen to continue to rise to the target supply temperature.

[0027] Specifically, the adjustment of the heat transfer fluid flow rate or the heat transfer fluid pump speed includes: calculating the target thermal power based on the liquid hydrogen supply flow rate and the total enthalpy change; calculating the actual input thermal power based on the heat transfer fluid inlet temperature and the heat transfer fluid outlet temperature; and using the deviation between the vaporized hydrogen outlet temperature and the target supply temperature as feedback quantity to perform closed-loop control of the heat transfer fluid regulating valve opening or the heat transfer fluid pump speed.

[0028] Specifically, the cold energy recovery heat exchanger is a plate heat exchanger, a coiled tube heat exchanger, or a printed circuit board heat exchanger. The cold energy recovery heat exchanger includes a hydrogen side channel and a refrigerant side channel, and non-contact heat exchange is performed between the hydrogen side channel and the refrigerant side channel.

[0029] Specifically, the refrigerant in the refrigerant circuit is one or more of silicone oil, ethylene glycol aqueous solution, fluorinated liquid, liquid nitrogen or cryogenic helium, and the refrigerant enters the cold energy distribution pipeline after being cooled by the cold energy recovery heat exchanger.

[0030] The hot-side flow channel and cold-side flow channel of the liquid hydrogen vaporizer and / or the hydrogen-side flow channel and refrigerant-side flow channel of the cold energy recovery heat exchanger are composed of high-throughput tubes. The high-throughput tubes include a pressure-bearing tube body and a metal-reinforced heat exchange layer disposed on the inner wall and / or outer wall of the pressure-bearing tube body. The metal-reinforced heat exchange layer is used to increase the effective heat exchange area to enhance the vaporization and boiling heat exchange of liquid hydrogen and the low-temperature convection heat exchange of hydrogen, heat transfer fluid or refrigerant.

[0031] Specifically, the cold energy distribution pipeline includes a precooler branch, a liquid hydrogen storage tank insulation branch, and a bypass cooling branch; the precooler branch connects the cold energy recovery heat exchanger to the hydrogen dispenser precooler, the liquid hydrogen storage tank insulation branch connects the cold energy recovery heat exchanger to the liquid hydrogen storage tank insulation heat exchange unit, and the bypass cooling branch connects the cold energy recovery heat exchanger to the dry cooler or the ambient heat dissipation unit.

[0032] Specifically, the precooler branch, the liquid hydrogen storage tank insulation branch, and the bypass cooling branch distribute cooling capacity through a three-way proportional regulating valve, a solenoid switch valve, or a combination thereof. When the hydrogen dispenser is in the refueling state, the precooler branch is opened and cooling capacity is distributed preferentially. When the hydrogen dispenser is not in the refueling state and the refrigerant outlet temperature is lower than a preset threshold, the liquid hydrogen storage tank insulation branch is opened. When the refrigerant circuit pressure exceeds the safety threshold or all cooling branches do not meet the opening conditions, the bypass cooling branch is opened.

[0033] Specifically, the heat storage device is connected in parallel or in series on the main heat-carrying fluid pipeline between the heat exchanger unit and the liquid hydrogen vaporizer. The heat storage device is a phase change heat storage device, a water heat storage device, a molten salt heat storage device, or a solid sensible heat storage device.

[0034] Specifically, the energy thermal management method is executed by a PLC controller or an industrial control computer. The PLC controller or industrial control computer coordinates and controls the working status of the heat transfer fluid pump, heat transfer fluid regulating valve, heat storage device switching valve, refrigerant circulation pump, and cold energy distribution valve based on the load signal of the computing center chip, the liquid hydrogen supply demand signal, the liquid hydrogen storage tank status signal, the hydrogen outlet temperature signal, the heat transfer fluid temperature signal, the refrigerant temperature signal, and the loop pressure signal.

[0035] Example 1: Multiple CVD artificial diamond sheets were sequentially attached to the outer wall of the inner tank, covering the entire surface of the inner tank. Each CVD artificial diamond layer was prepared using microwave plasma chemical vapor deposition, which significantly suppressed phonon scattering at liquid hydrogen temperatures. One side of the artificial diamond layer was connected using a low thermal resistance metallization welding process: three metallization films were first deposited sequentially on the diamond surface; then, gold-tin solder was applied to the outer wall of the inner tank, and the metallized diamond surface was eutecticly welded to the tank wall in a vacuum furnace. The interfacial thermal resistance after welding was tested using a laser scintillation method.

[0036] On the other side of the artificial diamond layer (towards the insulation layer), a copper microchannel array is constructed on its upper metallization layer using a photolithography-electroforming-bonding process. The microchannels have rectangular cross-sections; the microchannels are connected in parallel to collect current, which flows into the main refrigerant inlet and outlet manifolds respectively.

[0037] The inner wall of the microchannel array (i.e. the copper wall surface in contact with the refrigerant) is prepared with a porous coating by the following process: copper powder paste is coated onto the inner wall of the microchannel using screen printing, and then sintered in a reducing atmosphere furnace.

[0038] After penetrating the insulation layer, the heat leakage first reaches the outer surface of the artificial diamond layer. Due to the extremely high thermal conductivity of artificial diamond, this dispersed heat leakage is rapidly diffused in-plane and conducted to the bottom of the microchannel.

[0039] Liquid nitrogen was introduced into the microchannel array as a coolant. Due to the porous coating providing a large number of stable nucleation nuclei, the liquid nitrogen triggered nucleated boiling at the wall surface and entered the fully developed boiling region.

[0040] Under these conditions, almost all the heat leakage through the diamond layer is absorbed by the refrigerant and discharged from the outlet outside the tank. Only a trace amount of radiant heat may reach the liquid hydrogen body through the gaps in the refrigerant channel.

[0041] An oxygen-free copper transition layer is placed at the interface between the microchannel array and the artificial diamond layer. This transition layer is connected to the diamond surface via thermocompression bonding, and the microchannel array is connected to the transition layer via brazing. The elasto-plastic deformation of copper can absorb the thermal stress difference between the diamond and the stainless steel tank caused by temperature changes.

[0042] In this embodiment, taking a phase change gasifier with a rated heat exchange of 600kW as an example, the middle layer is a CVD artificial diamond sheet, and the two sides are oxygen-free copper encapsulation layers; the expression for the total thermal resistance network is: , Where U is the overall heat transfer coefficient, a measure of heat transfer capacity based on a reference area A; A is the reference heat transfer area, typically taken as A0. base (Projected area of ​​the partition wall) or the area of ​​one side of the cold / hot side is used as the calculation basis; therefore, UA combination is thermal conductivity, representing the heat power transferred per unit temperature difference; hh The convective heat transfer coefficient on the hot side is the convective heat transfer coefficient between the heat transfer fluid and the hot-side metal wall, which is enhanced by the microfin array; A h The actual heat transfer area on the hot side, i.e., the effective heat transfer area with micro-fin arrays processed on the hot side, t Cu k represents the thickness of a single-sided copper encapsulation layer. Cu A is the thermal conductivity of copper. base The thermal resistance is calculated based on the projected area of ​​the partition wall, i.e., the planar projected area of ​​the plate. diamond k is the thickness of the artificial diamond superconducting thermal layer. diamond h is the thermal conductivity of synthetic diamond. c A is the boiling heat transfer coefficient of liquid hydrogen on the cold side. c This represents the actual heat exchange area on the cold side, i.e., the total wetted area of ​​the cold-side microchannel array. Heat exchange satisfies: ; Q represents the heat exchange, ΔT m The logarithmic mean temperature difference; In the vaporizer, the hot and cold fluids are arranged in counter-current flow, and the temperature difference is calculated using the following formula: , Among them, T h,in T represents the inlet temperature of the heat transfer fluid. c,out T represents the outlet temperature of the cold fluid. h,out T represents the outlet temperature of the heat transfer fluid. c,in The inlet temperature of the cold fluid is given; the total thermal resistance is the series connection of the thermal resistances of each part, which is obtained by superimposing the thermal resistance of the hot-side convection heat transfer, the thermal resistance of the copper encapsulation layer, the thermal resistance of the artificial diamond superconducting thermal layer, and the thermal resistance of the cold-side liquid hydrogen boiling heat transfer. Countercurrent flow can achieve the maximum logarithmic mean temperature difference, which conforms to the basic equation of heat exchanger thermal design.

[0043] In this embodiment, the PID control of the heat transfer fluid flow rate is as follows: The control system collects data on tank pressure, hydrogen dispenser flow rate, heat transfer fluid inlet temperature, and hydrogen outlet temperature. An electrically operated regulating valve is installed on the main heat transfer fluid line, and its opening signal is output by a PID controller.

[0044] Feedforward calculation: Based on the real-time demand for hydrogen flow rate and tank pressure, the required heat power is calculated according to the total enthalpy change formula, and the basic flow rate is estimated based on the specific heat capacity of the heat transfer fluid and the rated supply and return water temperature difference. The difference between the actual measured hydrogen outlet temperature and the target filling temperature is used as the input of the PID controller to dynamically correct the basic flow rate. When the actual outlet temperature is higher than the target temperature, the regulating valve is closed to reduce the flow rate of the heat transfer fluid; conversely, the regulating valve is opened to increase the heat input, so that the hydrogen outlet temperature is stabilized within the preset target filling temperature range.

[0045] In one specific embodiment, the liquid hydrogen vaporizer and / or cold energy recovery heat exchanger employs a sintered high-flux tube bundle as an enhanced heat exchange unit. The sintered high-flux tube bundle includes multiple sintered high-flux heat exchange tubes, each of which includes a low-temperature hydrogen-compatible pressure-bearing tube body and a porous sintered metal layer disposed on the inner and / or outer walls of the pressure-bearing tube body.

[0046] The porous metal sintered layer is prepared using powder metallurgy, which involves attaching metal powder to the inner or outer surface of the pressure-bearing tube and sintering it to form a porous surface with a molten cavity structure. The pits and pores in this porous surface are interconnected, providing stable nucleation sites during liquid hydrogen vaporization. This allows liquid hydrogen to enter and maintain a nucleated boiling state at a relatively small heat exchange temperature difference, thereby improving the heat exchange stability of the liquid hydrogen vaporizer.

[0047] The porous metal sintered layer has a porosity of 50% to 70% and a thickness of 0.1 mm to 0.3 mm. For liquid hydrogen vaporizers, the porous metal sintered layer can be placed on the side in contact with liquid hydrogen to enhance the vaporization and boiling heat transfer of liquid hydrogen; for cold energy recovery heat exchangers, the porous metal sintered layer can be placed on the hydrogen side and / or the refrigerant side to increase the actual heat transfer area and disturb the near-wall fluid boundary layer, thereby improving the low-temperature convective heat transfer capacity.

[0048] Furthermore, the sintered high-flux heat exchange tube can be internally sintered, externally sintered, or a combination of internal and external sintering. When longitudinal grooves are provided on the outer surface of the sintered high-flux heat exchange tube, the longitudinal grooves work synergistically with the porous metal sintered layer to improve the liquid supply path and bubble detachment conditions, reduce the risk of localized drying, increase the critical heat flux density, and delay film boiling, thereby adapting to fluctuations in waste heat power, changes in liquid hydrogen supply flow, and fluctuations in hydrogen loading at the computing center.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content without departing from the scope of the present invention, forming equivalent embodiments with equivalent changes. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A thermal management method based on waste heat utilization and liquid hydrogen storage and transportation cold energy management in computing centers, characterized in that, include: S1: Obtain the waste heat generated by the liquid cooling heat dissipation circuit of the computing center, transfer the waste heat to the heat transfer fluid circuit through the heat exchanger group, and send the heat transfer fluid into the hot side flow channel of the liquid hydrogen vaporizer. S2: The liquid hydrogen output from the liquid hydrogen storage tank is sent into the cold side flow channel of the liquid hydrogen vaporizer, so that the heat transfer fluid and the liquid hydrogen exchange heat in the liquid hydrogen vaporizer, and the waste heat of the computing center is used to provide the heat required for vaporization and heating of the liquid hydrogen. S3: Real-time acquisition of liquid hydrogen supply flow rate, liquid hydrogen storage tank pressure, liquid hydrogen storage tank level, heat transfer fluid inlet temperature, and vaporized hydrogen outlet temperature, and adjustment of heat transfer fluid flow rate or heat transfer fluid pump speed based on total enthalpy change. S4: A cold energy recovery heat exchanger is installed downstream of the liquid hydrogen vaporizer to capture the cold energy released during the heating process of hydrogen from the cryogenic temperature and transfer the cold energy to the refrigerant circuit. S5: Selectively deliver the cooling capacity in the refrigerant circuit to at least one of the hydrogen precooler, the liquid hydrogen storage tank cold insulation branch, and the bypass cooling branch via the cold energy distribution pipeline; S6: When the waste heat power of the computing center is higher than the heat power required for the liquid hydrogen vaporization heating, the excess heat is stored in the heat storage device.

2. The thermal management method according to claim 1, characterized in that, The liquid cooling circuit of the computing center is a microchannel liquid cooling circuit of the AI ​​intelligent computing chip cluster. The heat carrier fluid is water, ethylene glycol aqueous solution, fluorinated liquid or insulating coolant. The heat carrier fluid circulates between the heat exchange unit and the liquid hydrogen vaporizer through a variable frequency magnetic drive pump.

3. The thermal management method according to claim 1, characterized in that, The hot and cold side channels of the liquid hydrogen vaporizer are arranged in a counter-current manner, and the flow direction of the heat transfer fluid is opposite to that of the liquid hydrogen.

4. The thermal management method according to claim 1, characterized in that, The heat transfer wall of the liquid hydrogen vaporizer includes a high thermal conductivity layer and metal encapsulation layers located on both sides of the high thermal conductivity layer. The surface of the hot-side metal encapsulation layer is provided with a micro-rib array that contacts the heat transfer fluid, and the surface of the cold-side metal encapsulation layer is provided with a microchannel array that contacts the liquid hydrogen.

5. The thermal management method according to claim 1, characterized in that, The total enthalpy change includes the sensible heat of liquid hydrogen as it rises from the tank temperature to the saturation temperature, the latent heat of vaporization required for liquid hydrogen to change from liquid to gas, and the sensible heat of gas required for the gaseous hydrogen to continue heating to the target supply temperature.

6. The thermal management method according to claim 1, characterized in that, The adjustment of the heat transfer fluid flow rate or the heat transfer fluid pump speed includes: calculating the target thermal power based on the liquid hydrogen supply flow rate and the total enthalpy change; calculating the actual input thermal power based on the heat transfer fluid inlet temperature and the heat transfer fluid outlet temperature; and using the deviation between the vaporized hydrogen outlet temperature and the target supply temperature as feedback quantity to perform closed-loop control of the heat transfer fluid regulating valve opening or the heat transfer fluid pump speed.

7. The thermal management method according to claim 1, characterized in that, The cold energy recovery heat exchanger is a plate heat exchanger, a coiled tube heat exchanger, or a printed circuit board heat exchanger. The cold energy recovery heat exchanger includes a hydrogen side channel and a refrigerant side channel, and non-contact heat exchange is performed between the hydrogen side channel and the refrigerant side channel.

8. The thermal management method according to claim 1, characterized in that, The refrigerant is cooled by the cold energy recovery heat exchanger and then enters the cold energy distribution pipeline. The hot side channel and cold side channel of the liquid hydrogen vaporizer and / or the hydrogen side channel and refrigerant side channel of the cold energy recovery heat exchanger are composed of high-throughput tubes. The high-throughput tubes include a pressure-bearing tube body and a metal-reinforced heat exchange layer disposed on the inner wall and / or outer wall of the pressure-bearing tube body. The metal-reinforced heat exchange layer is used to increase the effective heat exchange area to enhance the vaporization and boiling heat exchange of liquid hydrogen and the low-temperature convective heat exchange of hydrogen, heat transfer fluid or refrigerant.

9. The thermal management method according to claim 8, characterized in that, The high-throughput tube is a sintered high-throughput heat exchange tube, and the metal-reinforced heat exchange layer is a porous metal sintered layer formed on the inner wall and / or outer wall of the pressure-bearing tube by powder metallurgy. The porous metal sintered layer has interconnected cavities, pores and / or molten cave structures. Furthermore, the outer surface of the high-throughput tube can also be provided with longitudinal grooves to enhance liquid supply, bubble removal and near-wall fluid disturbance.

10. The thermal management method according to claim 1, characterized in that, The cold energy distribution pipeline includes a precooler branch, a liquid hydrogen storage tank insulation branch, and a bypass cooling branch; the precooler branch connects the cold energy recovery heat exchanger to the hydrogen dispenser precooler, the liquid hydrogen storage tank insulation branch connects the cold energy recovery heat exchanger to the liquid hydrogen storage tank insulation heat exchange unit, and the bypass cooling branch connects the cold energy recovery heat exchanger to the dry cooler or the ambient heat dissipation unit.

11. The thermal management method according to claim 10, characterized in that, The precooler branch, the liquid hydrogen storage tank insulation branch, and the bypass cooling branch are configured to distribute cooling capacity via a three-way proportional control valve, a solenoid valve, or a combination thereof. When the hydrogen dispenser is in the refueling state, the precooler branch is opened and prioritizes the distribution of cooling capacity. When the hydrogen dispenser is not in the refueling state and the refrigerant outlet temperature is below a preset threshold, the liquid hydrogen storage tank insulation branch is opened. When the refrigerant circuit pressure exceeds a safety threshold or none of the cooling branches meet the opening conditions, the bypass cooling branch is opened.

12. The thermal management method according to claim 1, characterized in that, The heat storage device is connected in parallel or in series on the main heat-carrying fluid pipeline between the heat exchanger unit and the liquid hydrogen vaporizer. The heat storage device is a phase change heat storage device, a water heat storage device, a molten salt heat storage device, or a solid sensible heat storage device.

13. The thermal management method according to claim 1, characterized in that, The energy thermal management method is executed and controlled by a PLC controller or an industrial control computer. The PLC controller or industrial control computer coordinates and controls the working status of the heat transfer fluid pump, heat transfer fluid regulating valve, heat storage device switching valve, refrigerant circulation pump, and cold energy distribution valve based on the load signal of the computing center chip, the liquid hydrogen supply demand signal, the liquid hydrogen storage tank status signal, the hydrogen outlet temperature signal, the heat transfer fluid temperature signal, the refrigerant temperature signal, and the loop pressure signal.

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