A fully autonomous self-adaptive heat pipe heat transfer performance testing method

Abstract

This invention belongs to the field of high-temperature heat pipe performance testing technology, specifically relating to a fully autonomous adaptive heat pipe heat transfer performance testing method. It includes the following steps: Step S1: Generating a heat flux density benchmark based on geometric features; Step S2: Using P... base Based on this, differentiated power loading is performed using a stage-dependent loading coefficient β. During step S2, steps S3 to S5 are executed in parallel: Step S3: Parallel execution of adaptive physical stage switching based on a dual criterion of "temperature-anomaly"; Step S4: Parallel execution of autonomous steady-state determination for each power loading at key temperature points in the linear heat transfer stage and during each power loading in the limit approximation stage; Step S5: Parallel execution of full-cycle automated safety protection based on monitoring the second derivative of the evaporation section temperature. The beneficial effects are: improved adaptability of the testing method, compatible with heat pipes of different geometric dimensions; and effective improvement of testing efficiency through the implementation of a staged control strategy.

Description

Technical Field

[0001] This invention belongs to the field of high-temperature heat pipe performance testing technology, specifically relating to a fully autonomous adaptive heat pipe heat transfer performance testing method. Background Technology

[0002] High-temperature heat pipes, with their superior passive thermal conductivity and isothermal properties, play a crucial role in advanced nuclear energy systems, deep space exploration, and thermal protection for supersonic vehicles. Before being deployed in practical engineering applications, heat pipes must undergo rigorous ground-based thermal testing to determine their heat transfer capacity, thermal resistance characteristics, and maximum heat transfer limit at different operating temperatures. Heat pipe performance test benches typically include heating, cooling, and monitoring and control systems. By gradually increasing the heating power and collecting data in real time, complete performance characteristic curves are plotted. Therefore, establishing a scientific and efficient method for testing heat transfer performance is of great significance for evaluating heat pipe quality, optimizing design parameters, and ensuring the safe operation of related thermal systems.

[0003] Existing heat pipe performance testing methods have accumulated a large amount of test data, and currently, the "fixed power step" loading mode is commonly used (e.g., increasing by a fixed 500W each time). However, this method has shown certain limitations when matching a large number of high-efficiency testing needs, mainly in the following aspects: First, a single loading mode is difficult to adapt to the differences in the geometry of different heat pipes. It cannot automatically match the appropriate heat flux density according to the length-to-diameter ratio or evaporation section area of ​​the heat pipe, which can easily cause overload of small-sized heat pipes or low testing efficiency of large-sized heat pipes.

[0004] Second: The fixed step size strategy is difficult to adapt to the physical evolution of the heat pipe at different operating stages throughout the test process. In the initial stage of startup, if the heating step size is too large or the temperature rises too quickly, the steam velocity is likely to reach the speed of sound and thus reach the speed of sound limit, resulting in the failure of the heat pipe startup. In the linear heat transfer zone after startup, the heat pipe works stably, and an overly conservative step size will lengthen the test cycle and increase energy consumption. In the high-temperature zone close to the heat transfer limit (such as the capillary limit), if the step size cannot be narrowed in time, it is easy to induce a sudden temperature rise, which not only makes it impossible to accurately capture the limit point, but also increases the risk of specimen damage.

[0005] Third: The steady-state determination and operating condition switching of heat pipes mainly rely on manual observation. The criteria for judging stability are greatly affected by subjective factors, resulting in poor data consistency.

[0006] Fourth: In high-risk areas close to the heat transfer limit, the lack of automatic trend prediction and protection mechanisms often results in significant damage to the heat pipes due to overheating before the operators can react. Summary of the Invention

[0007] The purpose of this invention is to provide a fully autonomous and adaptive heat pipe heat transfer performance testing method, aiming to solve the problems of existing testing technologies being unable to adapt to differences in heat pipe geometry and the evolution of physical characteristics across multiple stages of the heat pipe's lifecycle, and the high dependence of operating condition determination and safety protection on human experience. This invention achieves autonomous decision-making throughout the entire process, from parameter initialization to extreme condition determination, by automatically matching a suitable heat flux density benchmark based on the heat pipe's geometric characteristics, implementing differentiated step-size control based on different physical stages of heat pipe operation, and implementing autonomous steady-state determination and full-cycle safety protection. This significantly improves the efficiency, scientific rigor, and safety of high-temperature heat pipe heat transfer performance testing.

[0008] The “autonomy” mentioned in this invention refers to the fact that the entire testing process can complete parameter calculation, stage identification, operating condition switching, steady-state determination and safety protection without human intervention; the “adaptiveness” refers to the fact that the system dynamically matches the heat flux density reference and power loading step size according to the geometric characteristics and real-time operating status of the heat pipe under test.

[0009] The technical solution of the present invention is as follows: A fully autonomous adaptive heat pipe heat transfer performance testing method, comprising the following steps: Step S1: Generate a heat flux density benchmark based on geometric features; Based on the geometric characteristic parameters of the heat pipe under test, as well as the preset reference heat flux density increment q per unit area and geometric correction factor α, the reference power loading step size P applicable to the heat pipe is calculated. base ; Step S2: Dynamically identify the entire test process into three physical stages: the start-up stage, the linear heat transfer stage, and the limit approximation stage, and use P as the starting point. base Based on this, differentiated power loading is performed using a phase-dependent loading coefficient β; During the execution of step S2, steps S3 to S5 are executed in parallel. Step S3: During the execution of step S2, an adaptive physical phase switching based on the dual criteria of "temperature-anomaly" is performed in parallel. Step S4: During the execution of step S2, autonomous steady-state determination is performed in parallel for the key temperature points in the linear heat transfer stage and each power loading in the limit approximation stage. Step S5: During the execution of step S2, full-cycle automated safety protection based on the monitoring of the second derivative of the evaporation section temperature is executed in parallel.

[0010] The geometric feature parameters mentioned in step S1 include the total length L of the heat pipe, the pipe diameter D, and the evaporation section length L. e The effective heating area A and the reference power loading step P applicable to this specific heat pipe are calculated according to the following formula. base : A = π × D × L e, P base = q × A × α, In the formula: A is the effective heating area of ​​the heat pipe; D is the pipe diameter; L e q is the length of the evaporation section; α is the preset reference heat flux density increment per unit area; P is the geometric correction factor; base The reference power loading step size.

[0011] In step S1, the value of α ranges from 0.6 to 1.5.

[0012] In step S2, the entire process is dynamically identified into three stages: "start-up stage," "linear heat transfer stage," and "limit approximation stage," and a differentiated power loading function is executed. The heating power P for the (n+1)th heating cycle is... n+1 With the power P of the nth heating cycle n The relationship satisfies the following equation: P n+1 = P n + β × P base , In the formula: P n P is the power command value for the nth heating cycle. n+1 β is the heating power command value for the (n+1)th heating cycle; β is the staged loading coefficient; P base It is calculated from step S1.

[0013] The strategy for determining the value of the loading coefficient β in step S2 is as follows: Start-up phase: During the process of the heat pipe warming up from room temperature to full start-up, the value of β ranges from 0.4 to 0.8; Linear heat transfer stage: The steady-state heat transfer stage from the completion of heat pipe startup to approaching the target operating condition, the value of β ranges from 1.0 to 2.0; Limit Approach Stage: When the heat pipe approaches the target operating condition or an abnormal heat transfer phenomenon occurs, the value of β ranges from 0.1 to 0.5.

[0014] In step S3, adaptive physical stage switching is performed based on the dual criteria of "temperature-anomaly," including real-time monitoring of the average temperature T of the heat pipe insulation section. adb Based on the variation characteristics of the total thermal resistance R, determine the current stage of the heat pipe and execute corresponding differentiated step size control: Start-up phase: When the average temperature T of the adiabatic section adb Less than the preset transition temperature T trans At that time, it is determined that the heat pipe is in the start-up phase; Linear heat transfer stage: when the average temperature T of the adiabatic section adb Greater than or equal to T transIf no abnormal heat transfer phenomenon is detected, the heat pipe is determined to be in the linear heat transfer stage. Limit approximation stage: When any of the following conditions are met, the system is determined to have entered the limit approximation stage, and the heating step size is immediately switched: Condition A: Average temperature T of the adiabatic section adb Approaching the preset target operating temperature T target ; Condition B: Abnormal heat transfer characteristics are detected, specifically, the total thermal resistance R of the heat pipe increases by no less than 15% to 25% relative to the previous steady-state value; The formula for calculating the total thermal resistance R of a heat pipe is: , In the formula: and These represent the average temperatures of the evaporator section and the adiabatic section of the heat pipe, respectively; Q is the heat transfer power of the heat pipe; T trans The physical stage transition temperature is preset based on the characteristics of the working fluid.

[0015] Step S4 implements autonomous steady-state determination during critical stages, including during the linear heat transfer stage, whenever the average temperature T of the adiabatic section... adb Upon first reaching the preset critical temperature point, or after each power load during the extreme approach phase, the steady-state determination logic is initiated. The steady-state determination logic is as follows: within a preset duration Δt, the fluctuation amplitude ΔT of the temperature at the critical measuring point is monitored to see if it is less than the preset threshold ε. If it is, the steady-state condition is determined to have been reached, all critical parameters are recorded, and a command signal allowing the next level of loading is sent. If not, the current power is maintained until the steady-state criterion is met.

[0016] Step S5 implements automated safety protection throughout the entire testing cycle, including high-frequency sampling to monitor the second derivative of the evaporation section temperature with respect to time. Once it is detected that the second derivative is continuously positive and exceeds the preset overheating threshold, it is considered that the temperature is showing an exponential upward trend, and the protection mechanism is immediately triggered: heating is stopped and the cooling circuit is ensured to be opened to ensure the safety of the entire testing process.

[0017] The beneficial effects of this invention are as follows: 1) Improve the adaptability of the testing method and make it compatible with heat pipes of different geometric dimensions. This invention introduces a heat load adaptive mechanism based on geometric features. It can calculate the heat flux density benchmark applicable to a specific heat pipe based on the input parameters such as the total length, diameter, and evaporation section length of the heat pipe, using the principle of "equivalent heat flux density". This allows the same system to be compatible with the testing requirements of heat pipes of different sizes and heat transfer capabilities.

[0018] 2) Implementing a phased control strategy effectively improves testing efficiency. This invention dynamically identifies the entire testing process into three stages: the startup stage, the linear heat transfer stage, and the limit approximation stage, and executes differentiated power loading functions. Simultaneously, strict autonomous steady-state determination is implemented only at critical temperature points and during the limit approximation stage. This differentiated step-size control strategy, tailored to the characteristics of different physical stages, significantly shortens the overall testing cycle while ensuring the accuracy of key data.

[0019] 3) Achieve fully automated control throughout the entire process, ensuring data consistency and repeatability. This invention establishes an adaptive physical stage switching logic based on a dual criterion of "temperature-anomaly". The system automatically executes operating condition switching and loading based on objectively quantified indicators (such as the average temperature of the adiabatic section and the characteristics of thermal resistance changes), without manual intervention. This standardized, fully autonomous decision-making process eliminates subjective errors and uncertainties caused by human operation, ensuring the consistency and repeatability of test data.

[0020] 4) Enhanced real-time intelligent monitoring to ensure testing safety. This invention integrates a full-cycle safety protection mechanism. During the startup and limit approach phases, the loading coefficient is limited to prevent sound speed limits and temperature runaway. More importantly, the system monitors the second derivative of the evaporation section temperature using high-frequency sampling. Once the second derivative is detected to be continuously positive and exceed the preset temperature runaway threshold, heating is immediately and automatically stopped, and the cooling circuit is ensured to open, effectively protecting the safety of the heat pipe specimen. Attached Figure Description

[0021] Figure 1 The flowchart shows a fully autonomous adaptive heat pipe heat transfer performance testing method provided by this invention. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] The present invention provides a fully autonomous adaptive heat pipe heat transfer performance testing method, which aims to solve the problems that existing testing technologies are difficult to adapt to the differences in the geometric dimensions of different heat pipes and the evolution of physical characteristics in multiple stages throughout the entire cycle, and that the determination of operating conditions and safety protection are highly dependent on human experience, thereby improving the scientificity and safety of high-temperature heat pipe performance testing.

[0024] The system upon which this invention is implemented includes a heating module, a cooling module, a temperature acquisition module, and a data processing and control module. The heating module provides adjustable DC heating power to the heat pipe evaporation section; the cooling module includes a forced air-cooling or water-cooling circuit located outside the condensation section and a fan / pump speed control device; the temperature acquisition module includes multiple thermocouples located in the evaporation section, the insulation section, and the condensation section, as well as a high-frequency sampling data acquisition card with a sampling frequency of not less than 10Hz; the data processing and control module is an industrial control computer with corresponding control programs installed, responsible for calculating the algorithm described in this invention and issuing output commands to the heating and cooling modules.

[0025] The core of this invention, a fully autonomous adaptive heat pipe heat transfer performance testing method, lies in constructing a testing method capable of adapting to the geometric characteristics and real-time operating status of the heat pipe. Specifically, this invention ensures the matching between the heat flux density benchmark and the heat pipe size by introducing a geometric parameter correction mechanism; simultaneously, it implements a phased differentiated step-size control strategy for the physical characteristics of the heat pipe at different stages, such as startup, linear heat transfer, and limit approximation. The specific steps include: Step S1: Generate a heat flux density benchmark based on geometric features; Before the test begins, the operator enters the geometric characteristic parameters of the heat pipe to be tested. These geometric characteristic parameters include at least the total length L of the heat pipe, the pipe diameter D, and the evaporation section length L. e Based on the principle of "equivalent heat flux density", the data processing and control module automatically calculates the effective heating area A and the reference power loading step size P applicable to the specific heat pipe according to the following formula. base : A = π × D × L e , P base = q × A × α, In the formula: A is the effective heating area of ​​the heat pipe, in cm². 2 D is the pipe diameter, in cm; L e q represents the length of the evaporation section in cm; q is the preset reference heat flux density increment per unit area in W / (min·cm). 2 ), which is given by experimental experience for different working fluids (such as sodium, potassium, lithium, etc.); α is a geometric correction coefficient, dimensionless, used to correct for differences in heat transfer capacity of heat pipes with different aspect ratios and other parameters; P base The reference power loading step size is expressed in W / min.

[0026] The correction coefficient α follows the principle that "the smaller the aspect ratio, the larger the correction coefficient," to compensate for the physical characteristic that short and thick heat pipes have a stronger heat transfer capacity per unit area. In a preferred embodiment, the value of α ranges from 0.6 to 1.5.

[0027] Step S2: Perform differentiated step size control for each physical phase; After the test begins, the system monitors the heat pipe's operating status in real time, dynamically identifying the entire process into three stages: "start-up stage," "linear heat transfer stage," and "limit approximation stage," and executing differentiated power loading functions accordingly. The heating power P for the (n+1)th heating cycle... n+1 With the power P of the nth heating cycle n The relationship satisfies the following equation: P n+1 = P n + β × P base , In the formula: P n P is the power command value for the nth heating cycle. n+1 The power command value for the (n+1)th heating cycle is in W; β is the staged loading coefficient, dimensionless; P base It is calculated from step S1.

[0028] The strategy for determining the value of the loading coefficient β is as follows: ① Start-up phase: During the process of the heat pipe rising from room temperature to complete the start-up of the entire section, it is in the low temperature zone. In order to prevent reaching the speed of sound limit, the value of β is 0.4~0.8. ② Linear heat transfer stage: During the steady heat transfer stage from the completion of heat pipe startup to approaching the target operating condition, in order to improve efficiency, the value of β ranges from 1.0 to 2.0; ③ Limit Approach Stage: When the heat pipe approaches the target operating condition or an abnormal heat transfer phenomenon occurs, in order to accurately capture the failure point and prevent overheating, the value of β is in the range of 0.1~0.5.

[0029] Meanwhile, during the execution of step S2, the system executes the strategies described in steps S3 to S5 in parallel.

[0030] Step S3: Adaptive physical phase switching based on the dual criteria of "temperature-anomaly"; The system monitors the average temperature T of the heat pipe insulation section in real time. adb Based on the variation characteristics of the total thermal resistance R, the system automatically determines the current stage of the heat pipe and executes corresponding differentiated step size control: ① Start-up phase: When the average temperature T of the adiabatic section adb Less than the preset transition temperature T trans At that time, the system determines that the heat pipe is in the startup phase; ② Linear heat transfer stage: When the average temperature T of the adiabatic section adb Greater than or equal to T trans If no abnormal heat transfer phenomenon is detected, the system determines that the heat pipe is in the linear heat transfer stage. ③ Limit Approximation Stage: When any of the following conditions are met, the system determines that it has entered the limit approximation stage and immediately switches the heating step size: Condition A (Target Approximation): Average temperature T of the adiabatic section adb Approaching the preset target operating temperature T target ; Condition B (Limit Identification): Abnormal heat transfer characteristics are detected, specifically, the total thermal resistance R of the heat pipe increases significantly with increasing power, defined as an increase of not less than 15%~25% relative to the previous steady-state value.

[0031] The formula for calculating the total thermal resistance R of a heat pipe is: , In the formula: and T represents the average temperature of the evaporator section and the adiabatic section of the heat pipe, respectively, in °C; Q represents the heat transfer power of the heat pipe, in W; R is in °C / W. trans The physical transition temperature is preset based on the characteristics of the working fluid, and the empirical value for sodium heat pipes is approximately 500℃.

[0032] Step S4: Implement autonomous steady-state determination at critical stages; During the linear heat transfer phase, whenever the average temperature T of the adiabatic section... adb Upon first reaching a preset critical temperature point (e.g., 550℃, 600℃, 650℃), or after each power loading during the extreme approach phase, the system initiates steady-state determination logic. This steady-state determination logic involves monitoring whether the temperature fluctuation amplitude ΔT at key measuring points is less than a preset threshold ε (preferably 2~10℃) within a preset duration Δt (preferably 5~10 min). If so, a steady-state condition is determined, all key parameters (including heating power, temperature at each stage, thermal resistance, etc.) are recorded, and a command signal allowing the next stage of loading is sent. If not, the current power is maintained until the steady-state criterion is met.

[0033] Step S5: Implement automated safety protection throughout the entire testing cycle; Throughout the test, the system monitors the second derivative of the evaporation section temperature with respect to time using high-frequency sampling. Once the second derivative is detected to be consistently positive and exceed the preset overheating threshold, it is considered that the temperature is rising exponentially, and the system immediately triggers a protection mechanism: stopping the heating module output and ensuring that the cooling circuit is open to ensure the safety of the entire test process.

[0034] Example This embodiment uses a high-temperature sodium heat pipe for an advanced nuclear energy system as the test object, and applies the fully autonomous adaptive testing method described in this invention to evaluate its heat transfer performance.

[0035] Before the test begins, the operator enters the geometric parameters of the heat pipe to be tested: total length L = 250cm, pipe diameter D = 2cm, and evaporation section length L. e =55cm. The system is set to a reference heat flux density increment per unit area q = 0.12W / (min*cm). 2 (Empirical values ​​for sodium heat pipes), geometric correction factor α = 1.0. Calculated according to the preset algorithm in step S1: A = π × D × Le = π × 2 × 55 ≈ 345 cm 2 , P base = q × A × α = 0.12 × 345 × 1.0 ≈ 41.4 W / min, At the same time, the sound speed limit transition temperature is set. The temperature is 500℃ (an empirical value for sodium heat pipes), and the target operating condition is T. target The system operates at temperatures ranging from 700℃ to 750℃, with key temperature conditions during the linear heat transfer phase at 550℃, 600℃, and 650℃. The steady-state determination time window is Δt = 5 min, the steady-state temperature fluctuation threshold is ε = 5℃, and the runaway temperature threshold is θ = 100℃ / min. 2 .

[0036] Startup Phase (Low Temperature Zone): In the initial stage of testing, the system detects T adb If the temperature is below 500℃, it is determined to be in the startup phase. The loading coefficient β is set to 0.5, and the loading increment is β × P. base = 0.5 × 41.4 ≈ 20.7 W / min, the system heats in stages until T adb Exceeding 500℃.

[0037] Linear heat transfer stage (steady-state region): when T adb When the temperature exceeds 500℃, the system is determined to enter the linear heat transfer stage, the loading coefficient β is set to 1.0, and the loading increment is β × P. base = 1.0 × 41.4 ≈ 41.4 W / mi. The heat pipe begins to heat up rapidly. When T adb When the preset temperatures of 550℃, 600℃ and 650℃ are reached for the first time, the system automatically starts the steady-state judgment logic: only when the temperature fluctuation is less than 5℃ within 5 minutes, the system determines that thermal equilibrium has been reached, automatically records all steady-state data (power, temperature of each segment, thermal resistance) at the operating point, and sends a command signal to allow the next stage of loading.

[0038] Limit Approach Phase (High-Risk Zone): When T adbAfter reaching 690℃, approaching the target operating condition, the system switches to the limit approximation stage, with the loading coefficient β set to 0.5 and the loading increment at 20.7 W / min, approaching the target operating condition; when T adb When the temperature reached 710℃, the thermal resistance R was detected to increase by about 20% compared to the previous steady-state value, which is an abnormal heat transfer characteristic. The loading coefficient β was further set to 0.1~0.2, and the loading increment was about 4.1~8.3W / min. The system began to approach the true limit with a small increment.

[0039] During the subsequent third steady-state determination phase with increased heating power, the system detected that the second derivative of the evaporation section temperature exceeded the preset runaway temperature threshold of 100℃ / min. 2 This triggers the protection mechanism, cutting off the heating power supply and setting the cooling fan to full speed, thus protecting the heat pipe from physical melting and breaking through.

[0040] After the test, export the power, temperature, and thermal resistance data for the entire process, and list the steady-state data for key operating conditions. The maximum heat transfer limit power point is the last stable operating condition point before the protection is triggered.

Claims

1. A fully autonomous adaptive heat pipe heat transfer performance testing method, characterized in that, Includes the following steps: Step S1: Generate a heat flux density benchmark based on geometric features; Based on the geometric characteristic parameters of the heat pipe under test, as well as the preset reference heat flux density increment q per unit area and geometric correction factor α, the reference power loading step size P applicable to the heat pipe is calculated. base ; Step S2: Dynamically identify the entire test process into three physical stages: the start-up stage, the linear heat transfer stage, and the limit approximation stage, and use P as the starting point. base Based on this, differentiated power loading is performed using a phase-dependent loading coefficient β; During the execution of step S2, steps S3 to S5 are executed in parallel. Step S3: During the execution of step S2, an adaptive physical phase switching based on the dual criteria of "temperature-anomaly" is performed in parallel. Step S4: During the execution of step S2, autonomous steady-state determination is performed in parallel for the key temperature points in the linear heat transfer stage and each power loading in the limit approximation stage. Step S5: During the execution of step S2, full-cycle automated safety protection based on the monitoring of the second derivative of the evaporation section temperature is executed in parallel.

2. The fully autonomous adaptive heat pipe heat transfer performance testing method as described in claim 1, characterized in that: The geometric feature parameters mentioned in step S1 include the total length L of the heat pipe, the pipe diameter D, and the evaporation section length L. e The effective heating area A and the reference power loading step P applicable to this specific heat pipe are calculated according to the following formula. base : A = π × D × L e , P base = q × A × α, In the formula: A is the effective heating area of ​​the heat pipe; D is the pipe diameter; L e q is the length of the evaporation section; α is the preset increment of the reference heat flux density per unit area; P is the geometric correction factor; base The reference power loading step size.

3. The fully autonomous adaptive heat pipe heat transfer performance testing method as described in claim 2, characterized in that: In step S1, the value of α ranges from 0.6 to 1.

5.

4. The fully autonomous adaptive heat pipe heat transfer performance testing method as described in claim 1, characterized in that: In step S2, the entire process is dynamically identified into three stages: "start-up stage," "linear heat transfer stage," and "limit approximation stage," and a differentiated power loading function is executed. The heating power P for the (n+1)th heating cycle is... n+1 With the power P of the nth heating cycle n The relationship satisfies the following equation: P n+1 = P n + β × P base , In the formula: P n P is the power command value for the nth heating cycle. n+1 β is the heating power command value for the (n+1)th heating cycle; β is the staged loading coefficient; P base It is calculated from step S1.

5. The fully autonomous adaptive heat pipe heat transfer performance testing method as described in claim 4, characterized in that: The strategy for determining the value of the loading coefficient β in step S2 is as follows: Start-up phase: During the process of the heat pipe warming up from room temperature to full start-up, the value of β ranges from 0.4 to 0.8; Linear heat transfer stage: The steady-state heat transfer stage from the completion of heat pipe startup to approaching the target operating condition, the value of β ranges from 1.0 to 2.0; Limit Approach Stage: When the heat pipe approaches the target operating condition or an abnormal heat transfer phenomenon occurs, the value of β ranges from 0.1 to 0.

5.

6. The fully autonomous adaptive heat pipe heat transfer performance testing method as described in claim 1, characterized in that: In step S3, adaptive physical stage switching is performed based on the dual criteria of "temperature-anomaly," including real-time monitoring of the average temperature T of the heat pipe insulation section. adb Based on the variation characteristics of the total thermal resistance R, determine the current stage of the heat pipe and execute corresponding differentiated step size control: Start-up phase: When the average temperature T of the adiabatic section adb Less than the preset transition temperature T trans At that time, it is determined that the heat pipe is in the start-up phase; Linear heat transfer stage: when the average temperature T of the adiabatic section adb Greater than or equal to T trans If no abnormal heat transfer phenomenon is detected, the heat pipe is determined to be in the linear heat transfer stage. Limit approximation stage: When any of the following conditions are met, the system is determined to have entered the limit approximation stage, and the heating step size is immediately switched: Condition A: Average temperature T of the adiabatic section adb Approaching the preset target operating temperature T target ; Condition B: Abnormal heat transfer characteristics are detected, specifically, the total thermal resistance R of the heat pipe increases by no less than 15% to 25% relative to the previous steady-state value; The formula for calculating the total thermal resistance R of a heat pipe is: ， In the formula: and These represent the average temperatures of the evaporator section and the adiabatic section of the heat pipe, respectively; Q is the heat transfer power of the heat pipe; T trans The physical stage transition temperature is preset based on the characteristics of the working fluid.

7. The fully autonomous adaptive heat pipe heat transfer performance testing method as described in claim 1, characterized in that: Step S4 implements autonomous steady-state determination during critical stages, including during the linear heat transfer stage, whenever the average temperature T of the adiabatic section... adb Upon first reaching the preset critical temperature point, or after each power load during the extreme approach phase, the steady-state determination logic is initiated. The steady-state determination logic is as follows: within a preset duration Δt, the fluctuation amplitude ΔT of the temperature at the critical measuring point is monitored to see if it is less than the preset threshold ε. If it is, the steady-state condition is determined to have been reached, all critical parameters are recorded, and a command signal allowing the next level of loading is sent. If not, the current power is maintained until the steady-state criterion is met.

8. The fully autonomous adaptive heat pipe heat transfer performance testing method as described in claim 1, characterized in that: Step S5 implements automated safety protection throughout the entire testing cycle, including high-frequency sampling to monitor the second derivative of the evaporation section temperature with respect to time. Once it is detected that the second derivative is continuously positive and exceeds the preset overheating threshold, it is considered that the temperature is showing an exponential upward trend, and the protection mechanism is immediately triggered: heating is stopped and the cooling circuit is ensured to be opened to ensure the safety of the entire testing process.

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