Radiator performance testing device and method based on temperature stratification simulation analysis

Abstract

The invention belongs to the technical field of heat exchange of aircraft air source system equipment, and discloses a radiator performance testing device based on temperature stratification simulation analysis, which comprises a plate-fin radiator, and a temperature sensor and a pressure measuring nozzle are arranged on a hot side inlet pipe of the plate-fin radiator. A hot side outlet pipe of the plate-fin radiator is provided with a hot side outlet pressure measurer and a temperature sensor, a cold side inlet pipe of the plate-fin radiator is provided with a temperature sensor and a pressure measuring nozzle, and a cold side outlet pipe of the plate-fin radiator is provided with a cold side outlet pressure measurer and a temperature sensor; the rear end of the hot side outlet pipe is connected with a mixing pipe, and the rear end of the mixing pipe is provided with a temperature sensor. According to a CFD simulation plate-fin radiator outlet temperature distribution phenomenon, a test device is optimally designed, the radiator outlet temperature unevenness is reduced from 15% to 2% or below through a multi-section elbow turbulent flow structure, and three-dimensional distributed high-precision temperature measurement is achieved in cooperation with a depth-adjustable multi-section temperature sensor array.

Description

Technical Field

[0001] This invention belongs to the field of heat exchange technology for aircraft air source system equipment, and relates to a performance testing device and method for aircraft radiators, and a performance testing device and method for plate-fin radiators based on temperature stratification simulation analysis. Background Technology

[0002] Large air-to-air plate-fin radiators are widely used in aviation, energy, and electronics industries. As a crucial component of aircraft air supply systems, their heat exchange performance directly impacts the efficiency of system thermal management. The hot-side outlet temperature is a key parameter for evaluating the pressure regulation and temperature control design of the entire system. Traditional testing methods suffer from the following problems: Inaccurate measurement of the hot-side outlet temperature after heat exchange: Due to airflow mixing effects, heat exchanger outlet temperatures are prone to stratification, and single-point temperature measurements cannot reflect the true temperature magnitude. Flow field interference: Outlet pressure buildup or backflow causes flow field distortion, affecting the accuracy of heat exchange performance testing. Insufficient dynamic characteristic testing: Traditional steady-state testing cannot simulate the dynamic changes of actual operating conditions, such as flow fluctuations in the flight envelope. Inadequate sensor placement: A single sensor cannot comprehensively capture temperature stratification gradients. This patent aims to provide a plate-fin radiator performance testing device and method based on temperature stratification simulation analysis. Through multi-depth sensor arrangement and multi-bend pipe mixed flow optimization, it achieves high-precision heat transfer performance testing of radiators, providing reliable data support for the thermal management of air source systems or heat dissipation supporting systems. It has the advantages of high measurement accuracy, fast dynamic response and wide applicability. Summary of the Invention

[0003] To address the aforementioned issues, this invention provides a radiator performance testing device and method based on temperature stratification simulation analysis. By performing CFD simulation pre-analysis on the outlet temperature distribution characteristics of a large plate-fin radiator after heat exchange, the structure of the testing device and the sensor arrangement scheme are designed and optimized, thereby achieving accurate testing of the heat dissipation performance of a large plate-fin air-to-air radiator and providing reliable experimental data support for the thermal management of air source systems.

[0004] The technical solution of the present invention is as follows: A radiator performance testing device based on temperature stratification simulation analysis includes a plate-fin radiator. The hot-side inlet pipe of the plate-fin radiator is equipped with a temperature sensor and a pressure probe, the hot-side outlet pipe of the plate-fin radiator is equipped with a hot-edge outlet pressure probe and a temperature sensor, the cold-side inlet pipe of the plate-fin radiator is equipped with a temperature sensor and a pressure probe, and the cold-side outlet pipe of the plate-fin radiator is equipped with a cold-edge outlet pressure probe and a temperature sensor. A mixing pipe is also connected to the rear end of the hot-side outlet pipe, and a temperature sensor is also provided at the rear end of the mixing pipe.

[0005] Furthermore, the temperature sensors for the hot-side inlet pipe and the cold-side inlet pipe are single-point temperature sensors, while the temperature sensors for the hot-side outlet pipe and the cold-side outlet pipe are multi-point temperature sensors evenly distributed in a radial circle.

[0006] Furthermore, the pressure testing nozzles of the hot-side inlet pipe and the cold-side inlet pipe are single-point pressure testing nozzles, while the hot-side outlet pressure tester and the cold-side outlet pressure tester are multi-point pressure testers evenly distributed in a radial circle.

[0007] Furthermore, it also includes tie rods, heat insulation jackets, and support plates. The heat insulation jacket is wrapped around the outside of the plate-fin radiator, the support plate is placed between the two flanges at the top and bottom of the plate-fin radiator, and the tie rods are used to connect the flanges of the cold side inlet and outlet pipes and tighten the connection of the side inlet and outlet pipes.

[0008] Furthermore, the heat-insulating vest includes a three-layer structure: an outer alloy layer, a middle layer of heat-insulating ceramic fiber felt, and an inner aerogel flexible pad.

[0009] Furthermore, based on the area A of the outlet cross-section of the plate-fin radiator, the diameter D1 of the cold-side outlet pipe is 0.72A, which is 1 / 4D1. 2 ×π=A, the length of the cold side outlet pipe is not less than 10D1.

[0010] Furthermore, the mixing tube is a multi-section bend-pipe flow-disrupting structure. The inner diameter of the mixing tube is the same as that of the hot-side outlet tube, and the installation direction of the mixing tube is not the same as the fluid flow direction of the hot-side outlet tube. The mixing tube includes four 90° bends, and the end of the mixing tube is a straight tube. A temperature sensor is installed on the straight tube at the end of the mixing tube.

[0011] Furthermore, the temperature sensor of the straight pipe at the end of the mixing pipe is a multi-point temperature sensor that is evenly spaced along the axial and radial directions of the pipe, with a temperature measurement interval of no more than 0.3D2, where D2 is the diameter of the mixing pipe.

[0012] Furthermore, all temperature sensors are T-type thermocouples.

[0013] A method for testing radiator performance based on temperature stratification simulation analysis, using the aforementioned radiator performance testing device based on temperature stratification simulation analysis, includes the following steps: S1, Install the testing device and check for leaks in the testing device's piping; S2, Adjust test parameters; S3, conduct experiments and collect data, including hot edge inlet flow rate, hot edge inlet and outlet pressure, and hot edge inlet and outlet temperature; collect cold edge inlet flow rate, hot edge inlet and outlet pressure, and hot edge inlet and outlet temperature. S4 determines the outlet temperature and heat exchange efficiency. S5 is used for data analysis and performance evaluation of the radiator.

[0014] The technical effects of this invention are as follows: 1. Based on the CFD simulation of the outlet temperature distribution of plate-fin radiators, this invention optimizes the design of the experimental device: by using a multi-segment bent tube turbulence structure, the non-uniformity of the radiator outlet temperature is reduced from 15% to below 2%, and with the adjustable depth multi-section temperature sensor array, three-dimensional distributed high-precision temperature measurement is achieved.

[0015] 2. The system adopts a high-frequency response T-type thermocouple and a real-time data acquisition system to accurately test the dynamic characteristics of the radiator. The cold-side air device is designed with an anti-pressure venting structure to ensure flow field stability and reduce test deviation.

[0016] 3. Modular thermal vest, also known as a three-layer composite structure: stainless steel / ceramic fiber / aerogel, reduces environmental heat interference by 90%, and is easy to disassemble via magnetic fasteners with a temperature resistance of 1000℃ and fuse.

[0017] 4. Both the hot and cold side outlets are pressure tested using the Kent cavity multi-point sampling average pressure method. Multiple pressure taps are arranged circumferentially along the pipe diameter on the radiator outlet pipe for installing pressure sensors. Pressure is connected through a ring conduit to ensure the accuracy of the pressure test.

[0018] 5. The system improves the overall accuracy of radiator performance testing, and is particularly suitable for performance testing of large air-to-air medium plate-fin radiators for aviation, providing reliable data support for aircraft thermal management systems. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the installation and connection of the performance testing device for plate-fin radiators according to the present invention; Figure 2 This is a schematic diagram of the temperature distribution at the hot edge outlet section of a plate-fin radiator under a certain working condition. Figure 3 This is a schematic diagram of the temperature distribution along the central axis of the hot edge outlet of a plate-fin radiator under a certain operating condition. Figure 4 This is a schematic diagram of the mixing tube for the testing device of the present invention; Figure 5 This is a schematic diagram showing the installation position of the temperature sensor after the hot-side outlet mixing pipe in the testing device of this invention; Figure 6This is a schematic diagram of the insertion depth of the temperature sensor after the hot edge outlet mixing tube in the testing device of the present invention; Figure 7 This is a schematic diagram of the heat-insulating vest structure of the present invention; Figure 8 This is a schematic diagram of the distribution and installation of the pressure tapping holes for the hot edge outlet pressure test of the present invention (similar for the hot edge).

[0021] Among them, 1 is a plate-fin radiator, 2 is a hot-side outlet pressure sensor, 3 is a temperature sensor, 4 is a mixing pipe, 5 is a cold-side outlet pressure sensor, 6 is a pull rod, 7 is a pressure nozzle, 8 is a cold-side outlet pipe, 9 is a heat insulation vest, 10 is a support plate, 11 is a cold-side inlet pipe, 12 is a hot-side inlet pipe, 13 is a hot-side outlet pipe; 9a to 9l are different components of the heat insulation vest. Detailed Implementation

[0022] This section describes embodiments of the present invention, used to explain and illustrate the technical solutions of the present invention. Unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating directions or positional relationships, are given in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or device 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 of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include more than one of those features. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0024] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integrated connections; they can refer to mechanical connections or point connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] Example 1: A radiator performance testing device based on temperature stratification simulation analysis includes a plate-fin radiator 1. The hot-side inlet pipe 12 of the plate-fin radiator 1 is equipped with a temperature sensor and a pressure probe. The hot-side outlet pipe 13 of the plate-fin radiator 1 is equipped with a hot-side outlet pressure probe 2 and a temperature sensor. The cold-side inlet pipe 11 of the plate-fin radiator 1 is equipped with a temperature sensor and a pressure probe. The cold-side outlet pipe 8 of the plate-fin radiator 1 is equipped with a cold-side outlet pressure probe 5 and a temperature sensor. The rear end of the hot-side outlet pipe 13 is also connected to a mixing pipe 4, and the rear end of the mixing pipe 4 is also equipped with a temperature sensor.

[0026] Among them, the temperature sensors of the hot-side inlet pipe 12 and the cold-side inlet pipe 11 are single-point temperature sensors, while the temperature sensors of the hot-side outlet pipe 13 and the cold-side outlet pipe 8 are multi-point temperature sensors evenly distributed in a radial circle.

[0027] The pressure testing nozzles of the hot-side inlet pipe 12 and the cold-side inlet pipe 11 are single-point pressure testing nozzles, while the hot-side outlet pressure tester 2 and the cold-side outlet pressure tester 5 are multi-point pressure testers evenly distributed in a radial circle.

[0028] It also includes a tie rod 6, a heat insulation sleeve 9, and a support plate 10. The heat insulation sleeve 9 is wrapped around the outside of the plate-fin radiator 1. The support plate 10 is placed between the two flanges at the top and bottom of the plate-fin radiator 1. The tie rod 6 connects the flanges of the cold side inlet and outlet. The tie rod 6 is used to tighten the connection of the side inlet and outlet pipes.

[0029] The thermal vest 9 has a three-layer structure: an outer alloy layer, a middle thermal insulation ceramic fiber felt, and an inner aerogel flexible pad.

[0030] Based on the area A of the outlet cross-section of plate-fin radiator 1, the diameter D1 of the cold-side outlet pipe 8 is 0.72A, i.e., 1 / 4D1. 2 ×π=A, the length of the cold side outlet pipe 8 shall not be less than 10D1.

[0031] The mixing pipe 4 is a multi-section bend pipe turbulence structure. The inner diameter of the mixing pipe 4 is the same as that of the hot side outlet pipe 13. The installation direction of the mixing pipe 4 is not the same as the fluid flow direction of the hot side outlet pipe 13. The mixing pipe 4 includes four 90° bends. The end of the mixing pipe 4 is a straight pipe. A temperature sensor is installed on the straight pipe at the end of the mixing pipe 4.

[0032] The temperature sensor of the straight pipe at the end of the mixing pipe 4 is a multi-point temperature sensor that is evenly spaced along the axial and radial directions of the pipe, with a temperature measurement interval of no more than 0.3D2, where D2 is the diameter of the mixing pipe 4.

[0033] All temperature sensors are T-type thermocouples.

[0034] A method for testing radiator performance based on temperature stratification simulation analysis, using the aforementioned radiator performance testing device based on temperature stratification simulation analysis, includes the following steps: S1, Install the testing device and check for leaks in the testing device's piping; S2, Adjust test parameters; S3, conduct experiments and collect data, including hot edge inlet flow rate, hot edge inlet and outlet pressure, and hot edge inlet and outlet temperature; collect cold edge inlet flow rate, hot edge inlet and outlet pressure, and hot edge inlet and outlet temperature. S4 determines the outlet temperature and heat exchange efficiency. S5 is used for data analysis and performance evaluation of the radiator.

[0035] Example 2: Figure 1 The diagram shows a performance testing device for a plate-fin radiator based on temperature stratification simulation analysis. The device includes a plate-fin radiator 1, a hot-side outlet pressure gauge 2, a temperature sensor 3, a mixing pipe 4, a cold-side outlet pressure gauge 5, a tie rod 6, a pressure nozzle 7, a cold-side outlet pipe 8, a heat insulation jacket 9, a support plate 10, a cold-side inlet pipe 11, a hot-side inlet pipe 12, and a hot-side outlet pipe 13. Flow meters are installed in the hot and cold-side inlet pipes. The sensor signals from the pressure gauge, temperature sensor, and flow meters can be automatically acquired via a test bench. The heat insulation jacket 9 covers the exterior of the radiator 1. The support plate 10 is placed between the upper and lower flanges of the plate-fin radiator 1. When the tie rod 6 connects the cold-side inlet and outlet flanges to achieve a seal, the support plate 10 prevents deformation of the flanges. The plate-fin radiator 1 is wrapped with a heat insulation jacket 9 and a fuse is installed. A sealing gasket is installed between the plate-fin radiator 1 and the flanges of the cold side inlet pipe 11 and the cold side outlet pipe 8. During installation, the sealing gasket is tightly attached to the radiator flange, and the cold inlet and outlet pipes are tightened using a tie rod 6 to ensure a tight seal.

[0036] Figure 1 The cold-side outlet pipe 8 of the performance testing device shown is designed as a venting structure. Its pipe design is based on the area A of the outlet cross-section of the plate-fin radiator 1, with a diameter D1 = 0.72A (1 / 4D1...). 2 ×π=A), and the cold side outlet pipe 8 (the entire pipe length) is not less than 10D1, which avoids the influence of outlet pressure buildup on the air flow field and test results during the test and improves the stability of the flow field.

[0037] Figure 2 The diagram shows the temperature distribution at the hot-side outlet of the plate-fin radiator 1 under a certain heat exchange condition after thermal simulation analysis. It illustrates the temperature distribution at 20mm intervals along the cross-section from the initial position of the hot-side flange outlet. Figure 3The figure shows the temperature distribution along the central axis of the hot-side outlet of a plate-fin radiator 1 under a certain heat exchange condition, as analyzed by thermal simulation. It can be seen from the figure that the hot-side outlet temperatures at the same cross-section of the plate-fin radiator 1 differ significantly, with an initial temperature difference of approximately 200℃, indicating obvious stratification. This stratification persists along the central axis, and the degree of temperature difference does not change significantly. If traditional performance testing methods are used, without mixing the hot-side airflow, and temperature sensors are directly installed for measurement, inconsistent hot-side outlet temperature test results will occur due to varying sensor insertion depths and positions, resulting in significant deviations. Therefore, for air-to-air plate-fin radiators, CFD numerical simulation analysis is first used to obtain the temperature field distribution of the hot-side outlet cross-section under a certain heat exchange condition. This determines whether stratification exists and whether it is necessary to design bends, mixers, combined bends, or other turbulent mixing structures with mixed airflow to achieve accurate measurement of the outlet temperature after heat exchange.

[0038] Figure 4 The mixing pipe 4 at the hot-side outlet of the testing device of this invention is a multi-section bend pipe flow-disrupting structure. The bend pipe 4 is connected to the flange of the hot-side outlet pipe 13, and the pipes have the same inner diameter. The installation direction of the mixing pipe 4 is inconsistent with the fluid flow direction of the hot-side outlet pipe 13, thus changing the airflow direction once. The mixing pipe 4 consists of one bend pipe 4b, one straight pipe 4c, four bend pipes 4d, and one straight pipe 4e. The different pipes are argon arc welded together, and the weld positions are as follows. Figure 4 As shown, in order to verify the temperature stratification of the airflow before and after heat exchange in the radiator, four temperature sensors 3 were evenly distributed radially on the hot-side outlet pipe 13 and four temperature sensors 3 were evenly distributed radially on the straight pipe 4e in the mixing pipe 4. The temperature sensors at different positions were used to test the airflow temperature before and after mixing to verify the stratification and mixing effect. The inner walls of all pipes in the mixing pipe 4 were polished, and the combined bends achieved six changes in airflow direction to ensure full mixing of the hot-side outlet airflow and guarantee the uniformity of the test temperature.

[0039] Figure 5 This is a schematic diagram of the temperature sensor installation in the testing device of the present invention. Four temperature sensors 3 are evenly distributed radially along the straight pipe 4e in the mixing pipe 4 to measure the temperature of the airflow after mixing on the hot side. To avoid measurement errors caused by different installation positions and depths of the temperature sensors 3, the temperature sensors 3 are arranged separately along the axial and radial directions of the pipe. The axial temperature measurement spacing L1 does not exceed 0.3D2 (D2 is the pipe diameter), allowing for separate testing of the airflow temperature at different positions along the axial direction without causing temperature differences due to pipe length. (Refer to reference...) Figure 6The temperature sensors are evenly distributed along the pipe diameter at 360 degrees. The four sensors are spaced 90° apart to eliminate the influence of flow field asymmetry and to compensate for single-point installation deviations. The insertion depths are arranged alternately according to L2=1 / 3D2, L3=2 / 3D2, L2=1 / 3D2, and L3=2 / 3D2. During the test, the temperature sensors at different depths are marked. The 1 / 3D2 position captures the temperature of the boundary layer transition zone (approximately 0.1D2 from the wall), and the 2 / 3D2 position tests the temperature of the mainstream gas zone (representative area of ​​the core flow). The alternating insertion depths can capture the temperature gradient along the pipe diameter (such as the difference between the boundary layer and the core flow). At least four temperature sensors are set. After the mounting base of the temperature sensor 3 is welded, the perpendicularity of the mounting surface at the position where it mates with the sensor (perpendicular to the pipe diameter) is machined to ensure that the insertion angle of the temperature sensor is ≤0.5°. During the test, the temperature difference between different sensors cannot exceed ±2℃ to ensure the accuracy of the temperature measurement. During the performance testing of the plate-fin radiator 1, all temperature sensors 3 used T-type thermocouples with a response time of <10ms and a temperature measurement range of (-50~600)℃. The sensor signals were directly acquired through the test bench, with a sampling frequency of up to 1kHz. Furthermore, the temperature sensors 3 were installed using an adjustable and detachable sealed structure, and the exposed length of the sensor pins was adjustable, enabling convenient installation, measurement, maintenance, and adjustment.

[0040] Figure 7 This is a schematic diagram of the segmented composite heat insulation vest structure of the present invention. The heat insulation vest 9 is composed of different segmented structures designed according to the outer dimensions of the radiator. Figure 7 The showcased thermal insulation vest consists of 12 pieces ranging from 9a to 9l, all employing a three-layer composite insulation design: an outer stainless steel plate, a middle insulation layer made of ceramic fiber felt with a thermal conductivity ≤0.03W / m·K and a thickness of 8mm, and an inner aerogel flexible pad with a temperature resistance of 600℃, forming a highly efficient thermal barrier. It also features a quick-release mechanism, secured by a combination of magnetic snaps with a temperature resistance of 1000℃ and fuses. The 9f and 9g segments (each ≤300mm in length) of the thermal insulation vest accommodate different radiator sizes. Testing has verified that this structure reduces environmental thermal interference by 90%, and offers shorter assembly and disassembly times, increasing efficiency by 5 times compared to traditional insulation cotton wrapping. This design effectively isolates the internal medium of the radiator from heat exchange with the environment, ensuring the accuracy and repeatability of heat dissipation test results.

[0041] Figure 8This is a schematic diagram of the distribution and installation of pressure taps for the hot-side outlet pressure test in this invention. The hot-side outlet pressure tap 2 and the cold-side outlet pressure tap 5 are shown. In the testing device, both the hot and cold-side outlets are pressure tested using the Kent cavity multi-point sampling average pressure method. Specifically, multiple pressure taps (usually ≥4) are arranged circumferentially along the pipe diameter on the outlet pipe of the plate-fin radiator 1 for installing pressure sensors. Pressure communication is achieved through an annular cavity to ensure the accuracy of the pressure test. The diagram shows the installation positions of the four pressure taps evenly distributed along the pipe diameter at 360° intervals. The four sensors are spaced 90° apart. If there are more than four, they are evenly distributed along the pipe diameter at 360° intervals. The sensor spacing angle α = 360° / number of sensors. The sensors are connected through the annular cavity, and finally, a pressure sensor is led out at a certain pressure measurement position. The sensor signals can be automatically acquired through the test bench, achieving high-precision measurement of the airflow pressure at the hot and cold sides. The annular cavity can be made of rigid stainless steel or other materials.

[0042] The testing method for the plate-fin radiator performance testing device based on temperature stratification simulation analysis includes the following specific steps: Step S1: Installation of test fixtures and pipeline leak inspection a) Installation of cold edge testing fixture Wrap the plate-fin radiator 1 with the heat insulation sleeve 9 and secure the fuse. Connect the plate-fin radiator 1 to be tested to the test fixture (according to...). Figure 1 First, install the cold-side fixture (cold-side inlet pipe 11, cold-side outlet pipe 8). Place the support plate 10 between the upper and lower flanges of the plate-fin radiator 1. Install a gasket between the plate-fin radiator 1 and the flanges of the cold-side inlet pipe 11 and cold-side outlet pipe 8. During installation, ensure the gasket is tightly fitted to the radiator flanges and use the tie rod 6 to tighten the cold-side inlet and outlet pipes to ensure a tight seal. Follow the instructions... Figure 1 Install a cold-side flow meter, inlet and outlet pressure sensors, and temperature sensors.

[0043] b) Leakage inspection using cold edge testing fixtures Start the test bench, adjust the cold side flow rate, and gradually increase it to the maximum flow rate under test conditions. Check whether there is gas leakage between the plate-fin radiator 1 and the cold side inlet pipe 11 and the cold side outlet pipe 8. If there is leakage, reinstall the sealing gasket and the cold side inlet pipe 11 and the cold side outlet pipe 8, and tighten the pull rod 6 until there is no leakage.

[0044] c) Installation of hot edge testing fixture Connect the plate-fin radiator 1 to the hot-side test fixture (hot-side inlet pipe 12, hot-side outlet pipe 13) with clamps, and install the mixing pipe 4 after the hot-side outlet pipe 13, then bolt them together. Install the hot-side flow meter, inlet and outlet pressure sensors, and temperature sensors. Place copper gaskets (material resistant to temperatures up to 600℃) between the plate-fin radiator 1 and the hot-side inlet pipe 12, the hot-side outlet pipe 13, and the connecting flanges of the hot-side outlet pipe 13 and the mixing pipe 4 to ensure sealing. Figure 1 Install a hot-edge flow meter, inlet and outlet pressure sensors, and temperature sensors. d) Leakage inspection using hot edge testing fixtures Start the test bench, adjust the hot side flow rate, and gradually increase it to the maximum flow rate under test conditions. Check whether there is gas leakage between the plate-fin radiator 1 and the hot side inlet pipe 12, the hot side outlet pipe 13, and the connection between the hot side outlet pipe 13 and the mixing pipe 4. If there is leakage, reinstall the copper sealing gasket, use clamps to fix the connection, and tighten the bolts until there is no leakage.

[0045] Step S2: Debugging test parameters Operating condition simulation settings: Adjust parameters such as air flow, pressure and temperature at the hot and cold side inlets through the test bench, and observe whether there are any abnormal data. If there are no problems, proceed to the next formal test; otherwise, the sensor needs to be replaced or the installation needs to be checked.

[0046] Step S3: Experiment and Data Acquisition Multi-parameter synchronous monitoring: The test bench collects the inlet flow rate, inlet and outlet pressure, and inlet and outlet temperature of the hot side; it also collects the inlet flow rate, inlet and outlet pressure, and inlet and outlet temperature of the cold side. Among them, the temperature data measured by the four temperature sensors 3 evenly distributed radially on the straight pipe 4e in the mixing pipe 4 are the temperature results of the plate-fin radiator.

[0047] Step S4: Determine the outlet temperature and calculate the heat transfer efficiency η: η=(T1-T1′) / (T1-T2).

[0048] Where: T1—hot side inlet temperature; T1′—Hot side outlet temperature (the average value of data collected by four temperature sensors 3 evenly distributed radially on the straight pipe 4e in the mixing pipe 4). T2—Cold side inlet temperature.

[0049] Step S5: Data Analysis and Performance Evaluation η=(T1-T1′) / (T1-T2).

[0050] Where: T1—hot side inlet temperature; T1′—Hot side outlet temperature (the average value of data collected by four temperature sensors 3 evenly distributed radially on the straight pipe 4e in the mixing pipe 4). T2—Cold side inlet temperature.

[0051] Step S5: Data Analysis and Performance Evaluation To verify the temperature stratification of the airflow before and after heat exchange in the radiator, according to Figure 4 Four temperature sensors 3 are radially evenly distributed on the hot-side outlet pipe 13 and the straight pipe 4e of the mixing pipe 4 to collect data and verify the temperature stratification of the airflow before and after mixing in the radiator after heat exchange. In a test on a plate-fin radiator, the temperature difference collected by the four temperature sensors 3 on the mixing pipe 4 did not exceed 2℃, meeting the test requirements. This bent-pipe combination structure indicates thorough mixing. The temperature difference between the four temperature sensors 3 on the hot-side outlet pipe 13 is significant, with the minimum and maximum temperature differences differing by 200℃, which is in line with the requirements. Figure 2 The temperature stratification phenomenon was simulated and analyzed.

[0052] This invention provides a radiator performance testing device and method based on temperature stratification simulation analysis, mainly addressing the problems of insufficient temperature measurement accuracy and large flow field disturbance stratification in existing technologies. The patent utilizes CFD simulation to pre-analyze the outlet temperature distribution characteristics of a large plate-fin radiator after heat exchange, designing and optimizing the structure of the test device and the sensor arrangement. Multiple curved pipes are installed at the radiator outlet to achieve mixing, and several temperature sensors of varying depths and axial spacing are evenly distributed radially after the mixing pipes to accurately measure the outlet temperature after heat exchange, preventing the impact of temperature stratification. The cold-side outlet of the device adopts a direct venting design to avoid the influence of pressure buildup on the flow field. All temperature sensors use high-frequency response thermocouple sensors to improve dynamic testing accuracy and can achieve real-time acquisition of temperature, pressure, and flow data. The radiator is externally wrapped with a thermal insulation jacket, a three-layer composite insulation design, effectively isolating the internal medium of the radiator from heat exchange with the environment, ensuring the accuracy and repeatability of the heat dissipation test results. This invention achieves accurate testing of the heat dissipation performance of large plate-fin air-to-air radiators, providing reliable experimental data support for the thermal management of air source systems.

[0053] The temperature field distribution characteristics of the outlet section of the plate-fin radiator were obtained in advance by CFD numerical simulation. Based on this, the structural design of the test device was optimized. Multiple bends were set in the outlet section of the radiator to achieve full mixing of the outlet airflow. Multiple temperature sensors with different insertion depths (adjustable) and multi-section distribution arrays were arranged downstream to form a three-dimensional and distributed test. This design breaks through the limitations of traditional single-point or single-section temperature measurement and the measurement accuracy is greatly improved compared with traditional methods.

[0054] A mixing tube (a multi-segment bent pipe combination structure) was designed at the outlet of the testing device. The mixing tube is formed by welding multiple sections of bent pipe and straight pipe, and the inner wall is polished. The multi-bent pipe combination structure can fully mix the airflow, effectively solving the temperature stratification problem and reducing the cross-sectional temperature non-uniformity from 15% to below 2% (experimental data).

[0055] During the performance testing of the plate-fin radiator, the temperature sensors used to measure the air inlet and outlet temperatures are all type T thermocouples with a response time of <10ms and a temperature range of (-50~600)℃. The sensor signals can be directly acquired through the test bench, with a sampling frequency of up to 1kHz. The temperature sensors are installed using an adjustable and detachable sealed structure, ensuring both measurement accuracy and ease of maintenance and adjustment. This system achieves real-time dynamic acquisition of temperature parameters, improving dynamic testing capabilities by an order of magnitude compared to conventional systems.

[0056] Temperature sensors are arranged downstream of the hot-side outlet pipe of the test device. The temperature measurement interval between the temperature sensors does not exceed 0.3D (D is the diameter of the hot-side pipe). The installation positions of the temperature sensors are evenly distributed along the pipe diameter at 360 degrees. The 90° interval between the four sensors can eliminate the influence of flow field asymmetry and compensate for single-point installation deviations. The insertion depth is arranged alternately according to L2=1 / 3D2, L3=2 / 3D2, L2=1 / 3D2, and L3=2 / 3D2. The temperature sensors form a three-dimensional and distributed arrangement along the radial direction and the fluid flow direction. During the test, the temperature sensors at different depths are marked. The temperature of the boundary layer transition zone is captured at the 1 / 3D2 position (approximately 0.1D2 from the wall), and the temperature of the mainstream gas zone (representative area of ​​the core flow) is measured at the 2 / 3D2 position. Alternating insertion depths can capture the temperature gradient along the pipe diameter (such as the difference between the boundary layer and the core flow). At least four temperature sensors 3 are required. After the mounting base of the temperature sensor 3 is welded, the perpendicularity of the mounting surface at the position where it mates with the sensor (perpendicular to the pipe diameter) is machined to ensure that the insertion angle of the temperature sensor is ≤0.5°. During the test, the temperature difference between different sensors should not exceed ±2℃ to ensure the accuracy of the temperature measurement. During performance testing, the test bench data acquisition system can automatically collect inlet and outlet temperatures, flow rates, and pressure parameters of both hot and cold sides. The sampling frequency can reach 1kHz, and it supports data export and real-time monitoring, which greatly improves testing efficiency. In order to simulate the direct venting state on the machine and to test the pressure and temperature parameters at the inlet and outlet of the cold edge in the performance testing device, the test fixture was designed with a pipe of the same cross-sectional area as the outlet cross-section A of the plate-fin radiator. The pipe diameter D = 0.72A (1 / 4D). 2(×π=A), and the entire pipe length is not less than 10D, and it is directly discharged at the cold edge tooling outlet. The structural design of the cold edge outlet device avoids the influence of pressure buildup on the air flow field and test results, and improves the stability of the flow field.

[0057] Figure 7 This is a schematic diagram of the segmented composite heat insulation vest structure of the present invention. The heat insulation vest 9 is composed of different segmented structures designed according to the outer dimensions of the radiator. Figure 7 The showcased thermal insulation vest consists of 12 pieces ranging from 9a to 9l, all employing a three-layer composite insulation design: an outer stainless steel plate, a middle insulation layer made of 8mm thick ceramic fiber felt with a thermal conductivity ≤0.03W / m·K, and an inner aerogel flexible pad resistant to 600℃, forming a highly efficient thermal barrier. It also features a quick-release mechanism, secured with a combination of magnetic snaps and fuses resistant to 1000℃. The vest uses a segmented design (each segment ≤300mm long) to accommodate different radiator sizes. Testing has verified that this structure reduces environmental thermal interference by 90%, and offers shorter assembly and disassembly times, increasing efficiency by 5 times compared to traditional insulation cotton wrapping. This design effectively isolates the internal medium of the radiator from heat exchange with the environment, ensuring the accuracy and repeatability of heat dissipation test results.

[0058] In addition to non-standard flange connections used in traditional heat dissipation testing, this invention utilizes a tie rod clamping at both ends to achieve a tight seal on the test device. The flanges at both ends of the tie rod are connected to the radiator flanges via sealing gaskets. During testing, the tension of the tie rod can cause deformation of the radiator flanges. A support plate is installed between the flanges to prevent radiator deformation.

[0059] In the testing device of this invention, the Kent cavity multi-point sampling average pressure method is used for pressure testing at both the hot and cold side outlets. Multiple pressure taps (usually ≥4) are arranged circumferentially along the pipe diameter on the radiator outlet pipe for installing pressure sensors. Pressure communication is achieved through an annular cavity. The sensor is led out at a certain pressure measurement position and connected to the test bench to achieve data acquisition, realizing high-precision measurement of airflow pressure at both hot and cold sides. The above description is merely a specific embodiment of the present invention, providing a detailed description of the invention. Parts not covered herein are conventional techniques. However, the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. The scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A radiator performance testing device based on temperature stratification simulation analysis, characterized in that, The radiator includes a plate-fin radiator (1), a temperature sensor and a pressure probe are installed on the hot side inlet pipe (12) of the plate-fin radiator (1), a hot side outlet pressure probe (2) and a temperature sensor are installed on the hot side outlet pipe (13) of the plate-fin radiator (1), a temperature sensor and a pressure probe are installed on the cold side inlet pipe (11) of the plate-fin radiator (1), and a cold side outlet pressure probe (5) and a temperature sensor are installed on the cold side outlet pipe (8) of the plate-fin radiator (1); a mixing pipe (4) is also connected to the rear end of the hot side outlet pipe (13), and a temperature sensor is also provided at the rear end of the mixing pipe (4).

2. The radiator performance testing device based on temperature stratification simulation analysis according to claim 1, characterized in that, The temperature sensors of the hot-side inlet pipe (12) and the cold-side inlet pipe (11) are single-point temperature sensors, while the temperature sensors of the hot-side outlet pipe (13) and the cold-side outlet pipe (8) are multi-point temperature sensors evenly distributed in a radial circle.

3. The radiator performance testing device based on temperature stratification simulation analysis according to claim 1, characterized in that, The pressure testing nozzles of the hot-side inlet pipe (12) and the cold-side inlet pipe (11) are single-point pressure testing nozzles, while the hot-side outlet pressure tester (2) and the cold-side outlet pressure tester (5) are multi-point pressure testers evenly distributed in a radial circle.

4. The radiator performance testing device based on temperature stratification simulation analysis according to claim 1, characterized in that, It also includes a tie rod (6), a heat insulation vest (9) and a support plate (10). The heat insulation vest (9) is wrapped around the outside of the plate-fin radiator (1). The support plate (10) is placed between the two flanges at the top and bottom of the plate-fin radiator (1). The tie rod (6) connects the flanges of the cold side inlet and outlet. The tie rod (6) is used to tighten the connection of the side inlet and outlet pipes.

5. The radiator performance testing device based on temperature stratification simulation analysis according to claim 4, characterized in that, The heat-insulating vest (9) consists of three layers: an outer alloy layer, a middle layer of heat-insulating ceramic fiber felt, and an inner aerogel flexible pad.

6. The radiator performance testing device based on temperature stratification simulation analysis according to claim 1, characterized in that, Based on the area A of the outlet section of the plate-fin radiator (1), the diameter D1 of the cold-side outlet pipe (8) is 0.72A, i.e., 1 / 4D1. 2 ×π=A, the length of the cold side outlet pipe (8) is not less than 10D1.

7. The radiator performance testing device based on temperature stratification simulation analysis according to claim 1, characterized in that, The mixing pipe (4) is a multi-section bend pipe turbulence structure. The inner diameter of the mixing pipe (4) is the same as that of the hot side outlet pipe (13). The installation direction of the mixing pipe (4) is not the same as the fluid flow direction of the hot side outlet pipe (13). The mixing pipe (4) includes four 90° bends. The end of the mixing pipe (4) is a straight pipe. A temperature sensor is installed on the straight pipe at the end of the mixing pipe (4).

8. The radiator performance testing device based on temperature stratification simulation analysis according to claim 7, characterized in that, The temperature sensor of the straight pipe at the end of the mixing pipe (4) is a multi-point temperature sensor that is evenly spaced along the axial and radial directions of the pipe. The temperature measurement interval does not exceed 0.3D2, where D2 is the diameter of the mixing pipe (4).

9. The radiator performance testing device based on temperature stratification simulation analysis according to claim 1, characterized in that, All temperature sensors are T-type thermocouples.

10. A method for testing radiator performance based on temperature stratification simulation analysis, using a radiator performance testing device based on temperature stratification simulation analysis as described in any one of claims 1-9, characterized in that, Includes the following steps: S1, Install the testing device and check for leaks in the testing device's piping; S2, Adjust test parameters; S3, conduct experiments and collect data, including hot edge inlet flow rate, hot edge inlet and outlet pressure, and hot edge inlet and outlet temperature; collect cold edge inlet flow rate, hot edge inlet and outlet pressure, and hot edge inlet and outlet temperature. S4 determines the outlet temperature and heat exchange efficiency. S5 is used for data analysis and performance evaluation of the radiator.

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