Liquid metal high temperature pulsating heat pipe air cooling device and testing method

Abstract

The application provides a liquid metal high-temperature pulsating heat pipe air cooling device and a testing method. The device comprises a hot air blower, a dryer, a cooling chamber, a high-temperature pulsating heat pipe, a heating device, a temperature measuring device, a gas flow channel, a hygrometer, a pressure gauge, a gas mass flow meter, a cooler, a signal acquisition device and a data processing system. The hot air blower is connected with the cooling chamber, and the internal gas flow channel is formed. The evaporation section of the high-temperature pulsating heat pipe extends into the internal heating device, and the condensation section extends into the internal cooling chamber. The temperature measuring device is connected with the cooling chamber and the high-temperature pulsating heat pipe. The hygrometer, the gas mass flow meter and the pressure gauge are installed on the pipeline connected with the dryer and the cooling chamber. The cooler is connected with the cooling chamber and the sixth pipeline. The hygrometer, the pressure gauge, the gas mass flow meter and the temperature measuring device are connected with the signal acquisition device. The application can meet the cooling demand of the liquid metal high-temperature pulsating heat pipe in the heating environment above 1200 DEG C, and realizes the controllable air cooling environment of up to 400 DEG C.

Description

Technical Field

[0001] This invention relates to the field of pulsating heat pipe research technology, and more particularly to a liquid metal high-temperature pulsating heat pipe air-cooling device and testing method. Background Technology

[0002] First proposed in the 1990s, the pulsating heat pipe is a novel and highly efficient heat transfer element used to meet passive heat dissipation and heat collection needs in small spaces with high heat flux densities. Its excellent heat transfer performance has garnered significant attention. The main structure of a pulsating heat pipe includes an evaporation section, an adiabatic section, and a condensation section. The evaporation section is the heat-absorbing part, and the condensation section is the heat-releasing part. An adiabatic section is placed between the evaporation and condensation sections according to actual needs. Due to surface tension, the working fluid forms alternating liquid and gas plugs within the pipe. During operation, heat is transferred through the pipe wall to the working fluid in the evaporation section. Upon heating, nucleation boiling occurs on the wall surface. As heating progresses, nucleation boiling intensifies, with more bubbles forming, growing, and detaching at active nucleation sites. This increases the pressure and volume of the gas plugs, propelling the liquid plugs towards the condensation section. In the condensation section, the working fluid exchanges heat with the low-temperature wall surface, causing the gas plugs to contract or even rupture, reducing pressure. The liquid plugs, under the influence of gravity and the pressure difference between bends, flow back to the evaporation section, completing one working cycle. Currently, pulsed heat pipes have been applied in fields such as battery thermal management, industrial temperature-controlled furnaces, high-power LED lamp heat dissipation, data center cooling systems, and chip heat dissipation.

[0003] With the rapid development of hypersonic aircraft, nuclear thermal control, solar energy, and other high-temperature industrial fields, the problem of high heat flux conduction in high-temperature environments is increasingly restricting the development of cutting-edge equipment, creating an urgent need for components with good heat transfer performance in extreme high-temperature environments. Currently, extensive research has been conducted on low-temperature and room-temperature pulsating heat pipes operating in the range of -270℃ to 250℃, but very little has been applied to high-temperature fields. The invention of the liquid metal high-temperature pulsating heat pipe fills the gap in the application of pulsating heat pipes in high-temperature regions exceeding 500℃, extending the research and application of pulsating heat pipes to the high-temperature field and providing a new approach to solving the problems of high heat flux conduction and heat dissipation in high-temperature environments.

[0004] Considering the high-temperature application environment of high-temperature pulsating heat pipes, air cooling is an efficient and feasible method for their cooling. However, due to the characteristics of liquid metal working fluids and the significant challenges in high-temperature testing and application, current air-cooling devices for heat pipes and pulsating heat pipes are unsuitable for high-temperature pulsating heat pipes. There is a lack of forced convection cooling devices and methods for liquid metal high-temperature pulsating heat pipes, making it impossible to meet the testing and metrology requirements for liquid metal high-temperature pulsating heat pipes under the coupled influence of multiple factors such as wind speed, air volume, temperature, and humidity. It is also difficult to test average temperatures exceeding 500℃ and heat flux densities exceeding 1000 W / cm². 2Performance optimization of high-temperature pulsating heat pipes lacks a foundation for industrial applications. This invention provides a forced convection cooling device and method for liquid metal high-temperature pulsating heat pipes. Based on this device and method, the performance of high-temperature pulsating heat pipes under different wind speeds, air volumes, temperatures, and humidity conditions can be tested. During testing, the average temperature of the high-temperature pulsating heat pipe can exceed 500℃, and the heat flux density can exceed 1000 W / cm³. 2 Based on the application scenario, the influence of multiple factors is coupled to obtain an analysis and optimization index for the air-cooling performance of liquid metal high-temperature pulsating heat pipes based on the application scenario. By analyzing the air-cooling index, its heat transfer performance can be improved, laying the foundation for the research and application of high-temperature pulsating heat pipes. Summary of the Invention

[0005] The existing heat pipe and pulsating heat pipe air-cooling devices mentioned above are not suitable for high-temperature pulsating heat pipes. There is a lack of forced convection cooling devices and methods for liquid metal high-temperature pulsating heat pipes. Therefore, they cannot meet the testing and measurement requirements of liquid metal high-temperature pulsating heat pipes under the coupled influence of multiple factors such as wind speed, air volume, temperature, and humidity. It is also difficult to test heat pipes with average temperatures exceeding 500℃ and heat flux densities exceeding 1000 W / cm³. 2 To address the lack of fundamental technical issues in industrial applications for optimizing the performance of high-temperature pulsating heat pipes, this paper provides a liquid metal high-temperature pulsating heat pipe air-cooling device and testing method.

[0006] The technical means employed in this invention are as follows:

[0007] A liquid metal high-temperature pulsating heat pipe air-cooling device includes: a hot air blower, a dryer, a cooling chamber, a high-temperature pulsating heat pipe, a heating device, a temperature measuring device, a gas flow channel, a hygrometer, a pressure gauge, a gas mass flow meter, a cooler, a signal acquisition device, and a data processing system. The hot air blower, dryer, and cooling chamber are connected sequentially by pipes, forming a gas flow channel inside. The hot air blower provides cooling gas and is connected to the dryer through a first pipe. The dryer dries the cooling gas.

[0008] The heating device is connected to a high-temperature pulsating heat pipe, which is a liquid metal high-temperature pulsating heat pipe, including an evaporation section, an adiabatic section, and a condensation section. The evaporation section extends into the heating device to absorb heat, and the condensation section extends into the cooling chamber, where it is cooled by cooling gas. The adiabatic section is located between the evaporation section and the condensation section.

[0009] The temperature measuring device is connected to the cooling chamber and the high-temperature pulsating heat pipe, and is used to measure the wall temperature of the cooling chamber and the high-temperature pulsating heat pipe, as well as the temperature of the cooling gas flowing through the inlet and outlet of the cooling chamber.

[0010] The hygrometer, pressure gauge, and gas mass flow meter are sequentially installed on the pipe connecting the dryer and the cooling chamber. The hygrometer is located near the dryer and is used to measure the humidity of the current cooling gas. The gas mass flow meter is used to measure the mass flow rate of the cooling gas. The pressure gauge is used to measure the gas pressure inside the pipe and to calibrate the gas mass flow meter.

[0011] One side of the cooler is connected to the cooling chamber via a fifth pipe, and the other side is connected to a sixth pipe. The sixth pipe is connected to the external environment. The cooler is used to cool and filter the cooling gas. The gas treated by the cooler is discharged into the atmosphere through the sixth pipe.

[0012] The hygrometer, pressure gauge, gas mass flow meter, and temperature measuring device are connected to the signal acquisition device, which is in turn connected to the data processing system.

[0013] Furthermore, the temperature measuring device includes an RTD temperature sensor and multiple K-type thermocouples. At least two RTD temperature sensors are provided, distributed at the air inlet and air outlet on the front and rear sides of the cooling chamber, for measuring the temperature of the cooling gas at the air inlet and air outlet. At least four K-type thermocouples are arranged on both the inner and outer sides of the cooling chamber for measuring the inner and outer wall temperatures of the cooling chamber. At least three times the number of K-type thermocouples as bends are arranged on the outer surface of the high-temperature pulsating heat pipe for measuring the wall temperature of the high-temperature pulsating heat pipe.

[0014] Furthermore, the RTD temperature sensor, hygrometer, pressure gauge, and gas mass flow meter are all used to measure the center position data of the gas flow channel.

[0015] Furthermore, insulation cotton is arranged on the outside of the cooling chamber and each pipe, and the insulation section of the high-temperature pulsating heat pipe is wrapped with insulation cotton for insulation.

[0016] Furthermore, the hot air blower can control the exhaust temperature and exhaust volume, with the exhaust temperature range being 0 to 400°C and the exhaust volume being not less than 220 cubic meters per hour;

[0017] The cooling gas is a non-flammable and non-explosive gas, which is at least air, argon, or nitrogen.

[0018] Furthermore, the heating device is at least a heating furnace, a heating block, a heating wire, an induction heater, an infrared heating device, or a quartz lamp heating device, and the maximum temperature of the heating device using a high-temperature heating furnace can reach 1400℃.

[0019] Furthermore, the dryer is connected to the cooling chamber in sequence via a second pipe and a third pipe, and the cooling chamber uses a fourth pipe;

[0020] The hygrometer is installed on the second pipe to measure the humidity of the cooling gas at the second pipe; the gas mass flow meter is connected between the second pipe and the third pipe; the pressure gauge extends into the center of the second pipe to measure the gas pressure at the front end of the gas mass flow meter for calibrating the gas mass flow meter.

[0021] An inlet RTD temperature sensor and an outlet RTD temperature sensor are respectively installed at the inlet and outlet of the fourth pipe, and both the inlet RTD temperature sensor and the outlet RTD temperature sensor extend into the center of the fourth pipe.

[0022] The signal acquisition device employs a data acquisition system.

[0023] Furthermore, the high-temperature pulsating heat pipe can operate in environments above 500°C, transferring heat through working fluid oscillation; the structure of the high-temperature pulsating heat pipe is a closed serpentine array composed of bent high-temperature resistant metal tubes;

[0024] The working fluid of the high-temperature pulsating heat pipe is at least one of sodium, potassium, lithium, cesium, rubidium or mercury, or an alloy of more than one, wherein the proportion of each metal in the alloy is 0 to 100%.

[0025] The high-temperature pulsating heat pipe is at least in the form of a tubular pulsating heat pipe, a plate pulsating heat pipe, a shaped pulsating heat pipe, or a high-temperature pulsating heat pipe heat exchanger, and all forms include both open and closed types.

[0026] This invention also provides a testing method for a liquid metal high-temperature pulsating heat pipe air-cooling device, used to test the performance of a high-temperature pulsating heat pipe, comprising the following steps:

[0027] Step 1: Divide humidity, airflow, and temperature into x, y, and z gradients respectively;

[0028] Step 2: Start the hot air blower to supply air. Set the air volume and temperature according to the requirements. Start the dryer to dry the cooling gas. The humidity range can be controlled from 10% to 30%. Calibrate the gas mass flow meter according to the pressure. The data acquisition system records the data of the hygrometer, pressure gauge, gas mass flow meter, inlet RTD temperature sensor, outlet RTD temperature sensor, K-type thermocouples on the inner and outer surfaces of the fourth pipe, and K-type thermocouples on the surface of the high-temperature pulsating heat pipe in real time.

[0029] Step 3: Adjust the tilt angle of the high-temperature heating furnace and set it to low-power heating mode for warm-up. During the warm-up process, debug the K-type thermocouple, RTD temperature sensor, and data acquisition system. Set multiple heating power, heating temperature, and heating time for the high-temperature heating furnace to heat the high-temperature pulsating heat pipe. During the experiment, maintain a constant gas flow rate and temperature. After reaching the set temperature, record experimental data such as the temperature change of the high-temperature pulsating heat pipe and the temperature change of the cooling gas, and observe the operation of the relevant equipment.

[0030] Step 4: After the experiment, turn off the high-temperature heating furnace, lower the gas temperature to begin the cooling process, and complete a set of experiments;

[0031] Step 5: Based on actual needs, change the humidity, airflow, and temperature, and conduct at least x, y, and z sets of experiments. Each set of experiments should be repeated at least 3 times to comprehensively obtain data on the impact of cooling gas humidity, airflow, and temperature on the performance of the high-temperature pulsating heat pipe. Through data processing, obtain the influence law of the coupling effect of humidity, airflow, and temperature on the high-temperature pulsating heat pipe, understand the start-up and heat transfer performance of the high-temperature pulsating heat pipe under air-cooled conditions, and further optimize the heat transfer performance of the high-temperature pulsating heat pipe.

[0032] Furthermore, given the high temperature of the high-temperature heating furnace, a large amount of heat is leaked into the environment during the heating process. The electrical power of the high-temperature heating furnace cannot be equivalent to the input power of the high-temperature pulsating heat pipe. The heating power of the high-temperature pulsating heat pipe is calculated by measuring the heat transferred in the condensing section. The heating power includes the heat carried away by the air cooling and the heat leakage from the condensing section to the environment.

[0033] The input power of the high-temperature pulsating heat pipe satisfies the following formula:

[0034] Q e =Q w +Q d ;

[0035] Q w =(C p ) w q m (T p -T j );

[0036]

[0037] In the formula: Q e Q represents the heating power of a high-temperature pulsating heat pipe. w Q represents the heat carried away by the cooling gas in the condenser section of the high-temperature pulsating heat pipe. d For heat leakage in the condensation section, (C p ) w q is the specific heat capacity of the gas at the current temperature, obtained from a table based on humidity. mT is the mass flow rate of the cooling gas measured by the gas mass flow meter. p The temperature measured by the RTD temperature sensor at the air outlet tee, T j The temperature measured by the RTD temperature sensor at the air inlet tee, k d Let A be the thermal conductivity of the insulation material in the condensation section. d H represents the area of ​​the insulation layer, and H represents the thickness of the insulation layer. This represents the average temperature inside the insulation layer. This refers to the average external temperature of the insulation layer.

[0038] The heat flux density of the high-temperature pulsating heat pipe satisfies the following formula:

[0039]

[0040]

[0041] In the formula: Q e ′ represents the heat flux density of the high-temperature pulsating heat pipe, A represents the cross-sectional area of ​​the high-temperature pulsating heat pipe, N represents the number of bends, and D represents the heat flux density of the high-temperature pulsating heat pipe. o Outer diameter;

[0042] The thermal conductivity of the high-temperature pulsating heat pipe satisfies the following formula:

[0043]

[0044]

[0045] In the formula: k is the thermal conductivity of the high-temperature pulsating heat pipe, L eff L is the effective distance between the hot and cold ends. eva L adi and L con These are the lengths of the evaporation section, the adiabatic section, and the condensation section, respectively. The average temperature of the evaporation section. This represents the average temperature of the condensation section.

[0046] The thermal resistance of the high-temperature pulsating heat pipe satisfies the following formula:

[0047]

[0048] In the formula: R is the thermal resistance of the high-temperature pulsating heat pipe.

[0049] Compared with the prior art, the present invention has the following advantages:

[0050] 1. The liquid metal high-temperature pulsating heat pipe air-cooling device and testing method provided by this invention can meet the cooling requirements of liquid metal high-temperature pulsating heat pipes in heating environments above 1200℃, achieving a controllable air-cooling environment up to 400℃. The average temperature of the high-temperature pulsating heat pipe can exceed 500℃, and the heat flux density can exceed 1000W / cm². 2 .

[0051] 2. The liquid metal high-temperature pulsating heat pipe air-cooling device and testing method provided by the present invention have two RTD temperature sensors, a gas mass flow meter, a gas hygrometer, a pressure gauge, etc. installed before and after the air duct. The outside of the air duct is covered with multiple layers of heat insulation cotton, which can accurately measure the heat transfer performance under the influence of multiple factors such as wind speed, air volume, temperature, and humidity, and ensure that the heat leakage of the cooling part is less than 5%.

[0052] 3. Existing air-cooled devices for pulsed heat pipes can only control the cooling airflow speed, but cannot control the humidity and temperature of the air. In the research and application of pulsed heat pipes, humidity and temperature affect the mass, density, and specific heat capacity of air. The physical properties of air differ significantly under different humidity and temperature conditions, leading to substantial errors in research results obtained by controlling only the airflow speed. Especially in high-temperature environments, the humidity of the air has a greater impact on the performance and lifespan of the pulsed heat pipe. More importantly, the specific heat capacity of air is involved in the performance calculation of high-temperature pulsed heat pipes, making existing air-cooling technologies even less applicable. This invention overcomes the above shortcomings by controlling the airflow speed, humidity, and temperature of the cooled air through a hot air blower, dryer, hygrometer, and RTD temperature sensor, enabling the testing and performance calculation of high-temperature pulsed heat pipes under different air-cooling environments.

[0053] 4. Existing air-cooling testing methods only study the performance of room-temperature pulsating heat pipes under the influence of a single variable such as wind speed. These methods cannot achieve a controllable air-cooling environment up to 400℃, and cannot calculate heat transfer performance based on the heat transfer in the condenser section. Furthermore, during the application of pulsating heat pipes, their heat transfer performance is affected by the coupling of multiple factors such as wind speed, airflow, temperature, and humidity. Studying a single variable cannot provide a reference for performance optimization and application. The liquid metal high-temperature pulsating heat pipe forced convection cooling device and method provided by this invention can accurately measure multiple parameters such as wind speed, airflow, temperature, and humidity, and calculate the convective heat transfer coefficient based on the pipe layout. Using the convective heat transfer coefficient as an indicator of the forced convection cooling intensity, and analyzing the heat transfer performance of high-temperature pulsating heat pipes under the influence of the convective heat transfer coefficient, the heat transfer performance law of high-temperature pulsating heat pipes under the coupled influence of multiple air-cooling factors can be understood, thereby achieving optimization of the structure and performance of high-temperature pulsating heat pipes.

[0054] In summary, the liquid metal high-temperature pulsating heat pipe air-cooling device and performance testing method provided by this invention can solve the problem that existing pulsating heat pipe technologies cannot provide air-cooling conditions up to 400℃, thus pushing the air-cooling technology of pulsating heat pipes to high temperatures for the first time. It overcomes the shortcomings of existing technologies that can only control a single variable such as wind speed, and realizes the testing and optimization of high-temperature pulsating heat pipes under the coupled influence of multiple factors such as wind speed, air volume, temperature, and humidity.

[0055] Based on the above reasons, this invention can be widely applied in fields such as cooling with pulsating heat pipes. Attached Figure Description

[0056] 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 some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0057] Figure 1 This is a schematic diagram of the high-temperature pulsating heat pipe of the present invention.

[0058] Figure 2 This is a schematic diagram of the device of the present invention.

[0059] Figure 3 This is a schematic diagram (top view) of the convective heat transfer in the condensation section of the present invention.

[0060] In the diagram: 1. Hot air blower; 2. First pipe; 3. Dryer; 4. Hygrometer; 5. Second pipe; 6. Pressure gauge; 7. Gas mass flow meter; 8. Third pipe; 9. Inlet RTD temperature sensor; 10. Fourth pipe; 11. Data acquisition system; 12. High-temperature pulsating heat pipe; 13. Outlet RTD temperature sensor; 14. Fifth pipe; 15. Cooler; 16. Sixth pipe; 17. Data processing system; 18. High-temperature furnace; 19. Evaporation section; 20. Insulation section; 21. Condensation section. Detailed Implementation

[0061] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0062] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0064] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0065] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0066] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0067] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0068] like Figure 1-3 As shown, the present invention provides a liquid metal high-temperature pulsating heat pipe air-cooling device and a performance testing method.

[0069] In this invention, the high-temperature pulsating heat pipe 12 is a liquid metal high-temperature pulsating heat pipe that can operate in environments above 500°C, transferring heat through working fluid oscillation. The structure includes an evaporation section 19, an adiabatic section 20, and a condensation section 21, exhibiting a closed serpentine array composed of bent high-temperature resistant metal tubes. The high-temperature pulsating heat pipe 12 uses one of the following metals as the working fluid: sodium, potassium, lithium, cesium, rubidium, or mercury, or an alloy of more than one metal, with each metal comprising 0-100% of the alloy. The high-temperature pulsating heat pipe 12 can take the form of a tubular pulsating heat pipe, a plate pulsating heat pipe, a shaped pulsating heat pipe, or a high-temperature pulsating heat pipe heat exchanger, with all forms including both open and closed types.

[0070] The heating device for the high-temperature pulsating heat pipe can be a heating furnace, heating block, heating wire, induction heater, infrared heating, or quartz lamp heating. In this embodiment, the heating device is a high-temperature heating furnace 18.

[0071] The cooling medium (cooling gas) used in the high-temperature pulsating heat pipe forced convection cooling device (air-cooled device) and method is a non-flammable and non-explosive gas such as air, argon or nitrogen.

[0072] The high-temperature pulsating heat pipe forced convection cooling device of the present invention mainly includes: a high-temperature heating furnace 18, a high-temperature pulsating heat pipe 12, a K-type thermocouple, an RTD temperature sensor, a hot air blower 1, a gas mass flow meter 7, a hygrometer 4, a pressure gauge 6, a cooling chamber, a gas flow channel, and a signal acquisition device. The hot air blower 1 is connected to the cooling chamber via a pipe, forming a gas flow channel inside. The evaporation section 19 of the high-temperature pulsating heat pipe 12 extends into the high-temperature heating furnace 18, which can reach a maximum temperature of 1400℃. The insulation section 20 is insulated using insulating cotton. The condensation section 21 extends into the cooling chamber, and is cooled by the gas inside the cooling chamber. The cooling gas is supplied by the hot air blower 1, and the exhaust temperature and volume can be controlled. The exhaust temperature range of the hot air blower 1 is 0–400℃, and the exhaust volume is not less than 220 cubic meters per hour. The gas mass flow meter 7 is used to measure the mass flow rate of the cooling gas. The hygrometer 4 is used to measure the humidity of the current cooling gas. Pressure gauge 6 is used to measure the gas pressure inside the duct (the pipe near the hot air blower 1) to calibrate the gas mass flow meter 7. At least one RTD temperature sensor is placed before and after the cooling chamber (at the air inlet and outlet) to measure the temperature of the cooling gas. Insulation cotton is placed on the outside of the cooling chamber and each pipe to reduce heat leakage due to radiation. At least four K-type thermocouples are placed on both the inside and outside of the cooling chamber to measure the inner and outer wall temperatures. At least three times the number of K-type thermocouples as bends are placed on the outer surface of the high-temperature pulsating heat pipe 12 to measure the wall temperature of the high-temperature pulsating heat pipe 12 and calculate its heat transfer performance. The RTD temperature sensor, gas mass flow meter 7, hygrometer 4, and pressure gauge 6 are all used to measure the center position data of the gas flow channel.

[0073] The liquid metal high-temperature pulsating heat pipe air-cooling device of the present invention includes the aforementioned high-temperature pulsating heat pipe forced convection cooling device. Specifically, it includes: a dryer 3, a first pipe 2, a hygrometer 4, a hot air blower 1, a second pipe 5, a pressure gauge 6, a gas mass flow meter 7, a third pipe 8, an inlet RTD temperature sensor 9, a fourth pipe 10 (cooling chamber), a data acquisition system 11 (signal acquisition device), a high-temperature pulsating heat pipe 12, an outlet RTD temperature sensor 13, a fifth pipe 14, a cooler 15, a sixth pipe 16, a data processing system 17, and a high-temperature heating furnace 18. The high-temperature pulsating heat pipe 12 includes an evaporation section 19, an adiabatic section 20, and a condensation section 21, and its outer surface is fitted with at least three times the number of bends of K-type thermocouples to measure the wall temperature. The hot air blower 1, the dryer 3, and the fourth pipe 10 are connected sequentially through pipes, forming a gas flow channel inside. The outer surfaces of the second pipe 5, third pipe 8, fourth pipe 10, and fifth pipe 14 are wrapped with thermal insulation cotton to reduce heat leakage. At least four K-type thermocouples are installed on both the inner and outer surfaces of the fourth pipe 10 to measure the wall temperature. A hygrometer 4 measures the humidity at the inlet of the cooling gas pipe. The cooling gas is supplied by a hot air blower 1, which can control the exhaust temperature and volume. The exhaust temperature range of the hot air blower 1 is 0–400℃, and the exhaust volume is not less than 220 cubic meters per hour. A pressure gauge 6 measures the internal gas pressure of the second pipe 5; the pressure value is used to adjust the gas mass flow meter 7 to increase the accuracy of the mass flow rate. The gas mass flow meter 7 measures the mass flow rate of the cooling gas, with a flow range of 0–360 kg / h and a measurement accuracy of less than 0.2%. The inlet RTD temperature... Temperature sensor 9 and outlet RTD temperature sensor 13 are used to measure the temperature at the inlet and outlet of the fourth pipe 10; the data acquisition system 11 consists of hygrometer 4, pressure gauge 6, gas mass flow meter 7, inlet RTD temperature sensor 9, outlet RTD temperature sensor 13, K-type thermocouples on the inner and outer surfaces of the fourth pipe 10 and K-type thermocouples on the surface of the high-temperature pulsating heat pipe 12, and transmits the acquired data to the data processing system 17 through a data line for further data processing; the cooler 15 is used to cool the high-temperature cooling gas.

[0074] Hot air blower 1 supplies air to the air-cooling device and is connected to dryer 3 via first pipe 2. Dryer 3 is used to dry the cooling gas. Dryer 3 is connected to gas mass flow meter 7 via second pipe 5. Hygrometer 4 is located near dryer 3 and extends into the center of second pipe 5 to measure the humidity of the cooling gas at second pipe 5. Pressure gauge 6 is located between hygrometer 4 and gas mass flow meter 7 and extends into the center of second pipe 5 to measure the gas pressure at the front end of gas mass flow meter 7 for calibration. Gas mass flow meter 7 is connected to fourth pipe 10 via third pipe 8. Inlet RTD temperature sensor 9 and outlet RTD temperature sensor 13 are respectively installed at the inlet and outlet of fourth pipe 10 to measure high temperature pulses. The cooling gas temperatures before and after the heat pipe, the inlet RTD temperature sensor 9 and the outlet RTD temperature sensor 13 both extend into the center of the fourth pipe 10; the evaporation section 19 of the high-temperature pulsating heat pipe 12 extends into the high-temperature heating furnace 18 to absorb heat, the condensation section 21 extends into the interior of the fourth pipe 10 for cooling, and the insulation section 20 is located between the evaporation section 19 and the condensation section 21, and is wrapped with insulation cotton for insulation; the fourth pipe 10 is connected to the cooler 15 through the fifth pipe 14, and the cooler 15 is used to cool and filter the cooling gas; the gas treated by the cooler 15 is discharged to the atmosphere through the sixth pipe 16.

[0075] The forced convection device described above can control the heating temperature, heating rate, and heating power of the high-temperature pulsating heat pipe 12. By adjusting the heating program of the high-temperature heating furnace 18, multiple heating process parameters can be set, the heating rate and target furnace temperature can be adjusted and maintained, and the heating power can be kept constant after stable operation. The forced convection cooling device can control the inlet humidity, flow rate, and temperature of the cooling medium to ensure the stability of the cooling environment. The data acquisition system 11 and the data processing system 17 can accurately collect temperature changes, system heat leakage, and changes in the temperature of the cooling medium to meet various complex air-cooling test requirements in high-temperature environments.

[0076] The test method for the liquid metal high-temperature pulsating heat pipe air-cooling device of the present invention is used to perform performance testing on the high-temperature pulsating heat pipe 12. The specific test procedure is as follows:

[0077] Humidity, airflow, and temperature are divided into x, y, and z gradients, respectively. Hot air blower 1 is started to supply air, and the airflow and temperature are set according to requirements. Dryer 3 is started to dry the cooled gas, with humidity controllable within the range of 10% to 30%. Gas mass flow meter 7 is calibrated based on pressure. Data acquisition system 11 records in real time the data from hygrometer 4, pressure gauge 6, gas mass flow meter 7, inlet RTD temperature sensor 9, outlet RTD temperature sensor 13, the K-type thermocouples on the inner and outer surfaces of the fourth pipe 10, and the K-type thermocouples on the surface of the high-temperature pulsating heat pipe 12. The tilt angle of the high-temperature heating furnace 18 is adjusted to a low-power heating state for warm-up. During the warm-up process, the K-type thermocouples, RTD temperature sensors, and data acquisition system 11 are tested. Multiple heating power, heating temperature, and heating time are set for the high-temperature heating furnace 18, and the high-temperature pulsating heat pipe 12 is heated. During the experiment, gas flow and temperature are kept constant. After reaching the set temperature, record experimental data such as the temperature change of the high-temperature pulsating heat pipe 12 and the temperature change of the cooling medium, and observe the operation of related equipment. After the experiment, turn off the high-temperature heating furnace 18, lower the gas temperature to enter the cooling process, and complete one set of experiments. According to actual needs, change the humidity, air volume, and temperature, and conduct at least x·y·z sets of experiments, with each set of experiments repeated at least 3 times, to comprehensively obtain data on the influence of cooling gas humidity, air volume, and temperature on the performance of the high-temperature pulsating heat pipe 12. Through data processing, obtain the influence law of the coupling effect of humidity, air volume, and temperature on the high-temperature pulsating heat pipe 12, understand the start-up and heat transfer performance of the high-temperature pulsating heat pipe 12 under air-cooled conditions, and further optimize the heat transfer performance of the high-temperature pulsating heat pipe 12.

[0078] The average temperature of the high-temperature pulsating heat pipe 12 can exceed 500℃, and the heat flux density can exceed 1000W / cm³. 2 Because the high-temperature heating furnace 18 operates at a high temperature, it leaks a significant amount of heat into the environment during the heating process. Therefore, the electrical power of the high-temperature heating furnace 18 cannot be equivalent to the input power of the high-temperature pulsating heat pipe 12. The heating power of the high-temperature pulsating heat pipe 12 needs to be calculated by measuring the heat transferred by the condenser section 21. The heating power includes the heat carried away by the air cooling system and the heat leakage from the condenser section 21 into the environment. Therefore, the input power of the high-temperature pulsating heat pipe 12 can be obtained using the following formula:

[0079] Q e =Q w +Q d (1)

[0080] Q w =(C p ) w q m (T p -T j (2)

[0081]

[0082] In the formula: Q e Q represents the heating power of a high-temperature pulsating heat pipe. w Q represents the heat carried away by the cooling medium in the condensation section of a high-temperature pulsating heat pipe. d For heat leakage in the condensation section, (C p ) w The specific heat capacity of the gas at the current temperature needs to be obtained from a table based on the humidity, q. m T is the mass flow rate of the cooling medium measured by the gas mass flow meter. p The temperature measured by the RTD temperature sensor at the air outlet tee, T j The temperature measured by the RTD temperature sensor at the air inlet tee, k d Let A be the thermal conductivity of the insulation material in the condensation section. d H represents the area of ​​the insulation layer, and H represents the thickness of the insulation layer. This represents the average temperature inside the insulation layer. This represents the average temperature outside the insulation layer.

[0083] The heat flux density of the high-temperature pulsating heat pipe 12 can be obtained by the following formula:

[0084]

[0085]

[0086] In the formula: Q e ′ represents the heat flux density of the high-temperature pulsating heat pipe, A represents the cross-sectional area of ​​the high-temperature pulsating heat pipe, N represents the number of bends, and D represents the heat flux density of the high-temperature pulsating heat pipe. o It is the outer diameter.

[0087] The thermal conductivity of the high-temperature pulsating heat pipe 12 can be obtained by the following formula:

[0088]

[0089]

[0090] In the formula: k is the thermal conductivity of the high-temperature pulsating heat pipe, L eff L is the effective distance between the hot and cold ends. eva L adi and L con These are the lengths of the evaporation section, the adiabatic section, and the condensation section, respectively. The average temperature of the evaporation section. This represents the average temperature of the condensation section.

[0091] The thermal resistance of the high-temperature pulsating heat pipe 12 can be obtained by the following formula:

[0092]

[0093] In the formula: R is the thermal resistance of the high-temperature pulsating heat pipe.

[0094] The average convective heat transfer coefficient of the condensing section is calculated, and the air-cooling intensity index is determined.

[0095] In a liquid metal high-temperature pulsating heat pipe air-cooling device, the high-temperature pulsating heat pipe 12 exchanges heat with the cooling gas via convection, such as... Figure 3 The schematic diagram of convective heat transfer in the condensation section is shown. The high-temperature pulsating heat pipe 12 is placed perpendicularly to the air inlet of the fourth pipe 10, allowing the cooling gas to flow laterally into the pipe array. In the high-temperature pulsating heat pipe experiment, the high-temperature pulsating heat pipe 12 has a total of n bends, i.e., 2n pipes. First, the air velocity of the cooling gas flowing into the fourth pipe 10 is calculated:

[0096]

[0097] In the formula: u a A is the velocity of the cooling gas flowing into the air duct. f ρ is the cross-sectional area of ​​the pipe. f For the density of the cooling gas, ρ f Affected by humidity. The high-temperature pulsating heat pipe array is arranged in a single row, with a maximum wind speed u. max Appearing on the transverse plane of the pulsating heat pipe arrangement, according to the mass conservation requirements of incompressible fluids, we have:

[0098]

[0099] In the formula: S is the lateral spacing of the in-line tube cluster.

[0100] The next step is to calculate the maximum Reynolds number. According to the definition of the maximum Reynolds number, its expression is:

[0101]

[0102] In the formula: Re max denoted as the maximum Reynolds number, and μ as the kinematic viscosity of the cooling gas.

[0103] The average convective heat transfer coefficient of a high-temperature pulsating heat pipe is related to the Nusselt number. The Nusselt number is determined using the Jukkauska relation, which is related to the maximum Reynolds number and the Prandtl number. Within the temperature range of 0℃ to 400℃, the Prandtl number is greater than 0.6 and less than 500. The Nusselt number of the cooling gas is determined by the following relation:

[0104]

[0105] In the formula: Nu d For Nusselt numbers, These are the temperatures of the cooling gas measured by the RTD temperature sensor at the air inlet tee, specifically T. jAverage temperature of the condensation section Prandtl's number at that time.

[0106] Since the number of heat pipe rows in high-temperature pulsating heat pipes is 1, the Nusselt number needs to be corrected using the following formula:

[0107] Nu r =0.69Nu d (13)

[0108] In the formula: Nu r This is the corrected Nusselt number.

[0109] Average convective heat transfer coefficient The following formula can be used to obtain:

[0110]

[0111] In the formula: k a is the thermal conductivity of the cooling gas.

[0112] The average convective heat transfer coefficient is a test index for high-temperature pulsating heat pipes under the coupled influence of multiple factors such as wind speed, temperature, and humidity. Among these factors, wind speed affects the Reynolds number, while temperature and humidity mainly affect the density, viscosity, specific heat capacity, and thermal conductivity of the cooling gas. This leads to the understanding of the influence of the average convective heat transfer coefficient on the heat transfer performance of high-temperature pulsating heat pipes, and further optimization of the performance of high-temperature pulsating heat pipes under different cooling conditions.

[0113] The forced convection cooling device provided by this invention can meet the cooling requirements of liquid metal high-temperature pulsating heat pipes in heating environments above 1200°C, achieving a controllable air-cooled environment up to 400°C. The average temperature of the high-temperature pulsating heat pipe can exceed 500°C, and the heat flux density can exceed 1000 W / cm². 2 .

[0114] The liquid metal high-temperature pulsating heat pipe forced convection cooling device provided by the present invention has two RTD temperature sensors, a gas mass flow meter, a gas hygrometer, a pressure gauge, etc. installed before and after the air duct of its testing system. The outside of the air duct is covered with multiple layers of heat insulation cotton, which can accurately measure the heat transfer performance under the influence of multiple factors such as wind speed, air volume, temperature, and humidity, and ensure that the heat leakage of the cooling part is less than 5%.

[0115] Existing air-cooled devices for pulsed heat pipes can only control the cooling airflow speed, not the humidity and temperature of the air. In the research and application of pulsed heat pipes, humidity and temperature affect the mass, density, and specific heat capacity of air. Air properties vary significantly under different humidity levels and temperatures, leading to substantial errors in research results obtained by controlling only the airflow speed. This is especially true in high-temperature environments, where air humidity has a greater impact on the performance and lifespan of the pulsed heat pipe. More importantly, the specific heat capacity of air is involved in the performance calculations of high-temperature pulsed heat pipes, making existing air-cooling technologies even less applicable. This invention overcomes these shortcomings by controlling the airflow speed, humidity, and temperature of the cooled air using a hot air blower, dryer, hygrometer, and RTD temperature sensor, enabling the testing and performance calculation of high-temperature pulsed heat pipes under different air-cooling environments.

[0116] Existing air-cooling testing methods focus on the performance of room-temperature pulsating heat pipes under the single variable of wind speed. These methods cannot achieve a controllable air-cooling environment up to 400℃, nor can they calculate heat transfer performance based on the heat transfer in the condenser section. Furthermore, the heat transfer performance of pulsating heat pipes is influenced by the coupling effects of multiple factors such as wind speed, airflow, temperature, and humidity during application. Studying a single variable cannot provide a reference for performance optimization and application. The liquid metal high-temperature pulsating heat pipe forced convection cooling device and method provided by this invention can accurately measure multiple parameters such as wind speed, airflow, temperature, and humidity, and calculate the convective heat transfer coefficient based on the pipe layout. This convective heat transfer coefficient is used as an indicator of the intensity of forced convection cooling. By analyzing the heat transfer performance of high-temperature pulsating heat pipes under the influence of the convective heat transfer coefficient, the heat transfer performance law of high-temperature pulsating heat pipes under the coupled influence of multiple air-cooling factors can be understood, thus achieving optimization of the structure and performance of high-temperature pulsating heat pipes.

[0117] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A liquid metal high-temperature pulsating heat pipe air-cooling device, characterized in that, include: The system includes a hot air blower (1), a dryer (3), a cooling chamber, a high-temperature pulsating heat pipe (12), a heating device, a temperature measuring device, a gas flow channel, a hygrometer (4), a pressure gauge (6), a gas mass flow meter (7), a cooler (15), a signal acquisition device, and a data processing system (17). The hot air blower (1), the dryer (3), and the cooling chamber are connected in sequence by pipes, forming a gas flow channel inside. The hot air blower (1) is used to provide cooling gas and is connected to the dryer (3) through a first pipe (2). The dryer (3) is used to dry the cooling gas. The heating device is connected to a high-temperature pulsating heat pipe (12), which is a liquid metal high-temperature pulsating heat pipe, including an evaporation section (19), an adiabatic section (20), and a condensation section (21). The evaporation section (19) extends into the heating device to absorb heat, and the condensation section (21) extends into the cooling chamber, where the cooling gas in the cooling chamber cools the condensation section (21). The adiabatic section (20) is located between the evaporation section (19) and the condensation section (21). The temperature measuring device is connected to the cooling chamber and the high-temperature pulsating heat pipe (12) and is used to measure the wall temperature of the cooling chamber and the high-temperature pulsating heat pipe (12), as well as the temperature of the cooling gas flowing through the inlet and outlet of the cooling chamber. The hygrometer (4), pressure gauge (6), and gas mass flow meter (7) are installed sequentially on the pipe connecting the dryer (3) and the cooling chamber. The hygrometer (4) is close to the dryer (3) and is used to measure the humidity of the current cooling gas. The gas mass flow meter (7) is used to measure the mass flow rate of the cooling gas. The pressure gauge (6) is used to measure the gas pressure inside the pipe and to calibrate the gas mass flow meter (7). One side of the cooler (15) is connected to the cooling chamber through the fifth pipe (14), and the other side is connected to the sixth pipe (16). The sixth pipe (16) is connected to the external environment. The cooler (15) is used to cool and filter the cooling gas. The gas treated by the cooler (15) is discharged to the atmosphere through the sixth pipe (16). The hygrometer (4), pressure gauge (6), gas mass flow meter (7) and temperature measuring device are connected to the signal acquisition device, which is connected to the data processing system (17).

2. The liquid metal high-temperature pulsating heat pipe air-cooling device according to claim 1, characterized in that, The temperature measuring device includes an RTD temperature sensor and multiple K-type thermocouples. At least two RTD temperature sensors are provided, distributed at the air inlet and air outlet on the front and rear sides of the cooling chamber, for measuring the temperature of the cooling gas at the air inlet and air outlet. At least four K-type thermocouples are arranged on both the inner and outer sides of the cooling chamber for measuring the inner and outer wall temperatures of the cooling chamber. At least three times the number of K-type thermocouples as elbows are arranged on the outer surface of the high-temperature pulsating heat pipe (12) for measuring the wall temperature of the high-temperature pulsating heat pipe (12).

3. The liquid metal high-temperature pulsating heat pipe air-cooling device according to claim 2, characterized in that, The RTD temperature sensor, hygrometer (4), pressure gauge (6) and gas mass flow meter (7) are all used to measure the center position data of the gas flow channel.

4. The liquid metal high-temperature pulsating heat pipe air-cooling device according to claim 1, characterized in that, The cooling chamber and the outside of each pipe are covered with insulation cotton, and the insulation section (20) of the high-temperature pulsating heat pipe (12) is wrapped with insulation cotton for insulation.

5. The liquid metal high-temperature pulsating heat pipe air-cooling device according to claim 1, characterized in that, The hot air blower (1) can control the exhaust temperature and exhaust volume. The exhaust temperature range is 0~400℃ and the exhaust volume is not less than 220 cubic meters per hour. The cooling gas is a non-flammable and non-explosive gas, which is at least air, argon, or nitrogen.

6. The liquid metal high-temperature pulsating heat pipe air-cooling device according to claim 1, characterized in that, The heating device, when using a high-temperature heating furnace (18), can reach a maximum temperature of 1400℃.

7. The liquid metal high-temperature pulsating heat pipe air-cooling device according to claim 1, characterized in that, The dryer (3) is connected to the cooling chamber in sequence through the second pipe (5) and the third pipe (8), and the cooling chamber uses the fourth pipe (10). The hygrometer (4) is installed on the second pipe (5) to measure the humidity of the cooling gas at the second pipe (5); the gas mass flow meter (7) is connected between the second pipe (5) and the third pipe (8); the pressure gauge (6) extends into the center of the second pipe (5) to measure the gas pressure at the front end of the gas mass flow meter (7) in order to calibrate the gas mass flow meter (7); An inlet RTD temperature sensor (9) and an outlet RTD temperature sensor (13) are respectively arranged at the inlet and outlet of the fourth pipe (10). Both the inlet RTD temperature sensor (9) and the outlet RTD temperature sensor (13) extend into the center of the fourth pipe (10). The signal acquisition device adopts a data acquisition system (11).

8. The liquid metal high-temperature pulsating heat pipe air-cooling device according to any one of claims 1-7, characterized in that, The high-temperature pulsating heat pipe (12) can operate in environments above 500°C and transfer heat through working fluid oscillation; the structure of the high-temperature pulsating heat pipe (12) is a closed serpentine array composed of bent high-temperature resistant metal tubes; The working fluid of the high-temperature pulsating heat pipe (12) is at least one of sodium, potassium, lithium, cesium, rubidium or mercury, or an alloy of more than one, wherein the proportion of each metal in the alloy is 0 to 100%.

9. A test method for a liquid metal high-temperature pulsating heat pipe air-cooled device as described in claim 8, used for performance testing of the high-temperature pulsating heat pipe (12), characterized in that, Includes the following steps: Step 1: Divide humidity, airflow, and temperature into x, y, and z gradients respectively; Step 2: Start the hot air blower (1) to supply air, set the air volume and temperature according to the requirements, start the dryer (3) to dry the cooling gas, and control the humidity range of 10%~30%. According to the pressure, calibrate the gas mass flow meter (7). The data acquisition system (11) records the K-type thermocouple data on the inner and outer surfaces of the hygrometer (4), pressure gauge (6), gas mass flow meter (7), air inlet RTD temperature sensor (9), air outlet RTD temperature sensor (13), and the K-type thermocouple data on the surface of the high temperature pulsating heat pipe (12) of the fourth pipe (10) in real time. Step 3: Adjust the tilt angle of the high-temperature heating furnace (18) and set it to low power heating mode for warm-up. During the warm-up process, debug the K-type thermocouple, RTD temperature sensor and data acquisition system (11); set multiple heating power, heating temperature and heating time of the high-temperature heating furnace (18) to heat the high-temperature pulsating heat pipe (12). During the experiment, the gas flow rate and temperature are kept constant; after reaching the set temperature, record the experimental data of temperature change of high-temperature pulsating heat pipe (12) and temperature change of cooling gas, and observe the operation of related equipment. Step 4: After the experiment, turn off the high-temperature heating furnace (18), lower the gas temperature to enter the cooling process, and complete a set of experiments; Step 5: According to actual needs, change humidity, air volume and temperature, conduct at least one set of experiments, and repeat each set of experiments at least 3 times to obtain comprehensive data on the influence of cooling gas humidity, air volume and temperature on the performance of high temperature pulsating heat pipe (12). Through data processing, obtain the influence law of the coupling effect of humidity, air volume and temperature on high temperature pulsating heat pipe (12), master the start-up and heat transfer performance of high temperature pulsating heat pipe (12) under air-cooled conditions, and further optimize the heat transfer performance of high temperature pulsating heat pipe (12).

10. The test method for the liquid metal high-temperature pulsating heat pipe air-cooling device according to claim 9, characterized in that, Based on the high temperature of the high temperature heating furnace (18), a large amount of heat is leaked into the environment during the heating process. The electric power of the high temperature heating furnace (18) cannot be equivalent to the input power of the high temperature pulsating heat pipe (12). The heating power of the high temperature pulsating heat pipe (12) is calculated by measuring the heat transferred by the condensing section (21). The heating power includes the heat carried away by the air cooling and the heat leakage from the condensing section (21) to the environment. The input power of the high-temperature pulsating heat pipe (12) satisfies the following formula: ； ； ； In the formula: This refers to the heating power of a high-temperature pulsating heat pipe. This refers to the heat carried away by the cooling gas in the condensation section of the high-temperature pulsating heat pipe. For heat leakage in the condensation section, The specific heat capacity of the gas at the current temperature is obtained from a table based on humidity. The mass flow rate of the cooling gas measured by the gas mass flow meter. The temperature measured by the RTD temperature sensor at the air outlet tee. The temperature measured by the RTD temperature sensor at the air inlet tee. The thermal conductivity of the insulation material in the condensation section. For the area of ​​the insulation layer, For the thickness of the insulation layer, This represents the average temperature inside the insulation layer. This refers to the average external temperature of the insulation layer. The heat flux density of the high-temperature pulsating heat pipe (12) satisfies the following formula: ； ； In the formula: This refers to the heat flux density of a high-temperature pulsating heat pipe. This refers to the cross-sectional area of ​​the high-temperature pulsating heat pipe. Number of bends Outer diameter; The thermal conductivity of the high-temperature pulsating heat pipe (12) satisfies the following formula: ； ； In the formula: The thermal conductivity of the high-temperature pulsating heat pipe is... The effective distance between the hot and cold ends. , and These are the lengths of the evaporation section, the adiabatic section, and the condensation section, respectively. The average temperature of the evaporation section. This represents the average temperature of the condensation section. The thermal resistance of the high-temperature pulsating heat pipe (12) satisfies the following formula: ； In the formula: This refers to the thermal resistance of a high-temperature pulsating heat pipe.

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