基于热电偶的低速风洞气流温度误差补偿方法  

The error compensation method of the low-speed wind tunnel flow temperature based on the thermocouple

作　　者：杨兆欣 顾正华[1] 张文清[1] 曾星 Yang Zhaoxin;Gu Zhenghua;Zhang Wenqing;Zeng Xing(Facility Design and Instrumentation Institute of China Aerodynamics Research and Development Center,Mianyang 621000 China)

机构地区：[1]中国空气动力研究与发展中心设备设计与测试技术研究所,绵阳621000

出　　处：《仪器仪表学报》2022年第5期68-76,共9页Chinese Journal of Scientific Instrument

摘　　要：低速风洞气流温度数据质量是影响风洞流场品质的关键,针对热电偶测量导热误差和辐射误差补偿方法开展了专项研究。具体基于传热学基本原理,开展了基于热电偶丝浸入长度定值导热误差补偿方法、周围温度相对变化率定值辐射误差补偿方法研究,得到了热电偶浸入长度和周围温度相对变化率与温度测试误差之间定量关系的仿真结果。为了对于误差机理分析和仿真结果进行验证,开展了风洞验证试验。试验结果表明:热电偶浸入误差实测结果与理论仿真结果基本一致,周围温度相对变化率ω<1,可以降低温度测量辐射误差对于温度均匀性影响7.12倍。所提方法对于气体介质条件下热电偶工程应用提供了有益探索和技术依据。The quality of flow temperature data in the low-speed wind tunnel is the key to the character of the flow field of the wind tunnel.This article carries out special research on the compensation method of thermal conductivity error and radiation error in thermocouple measurement.Based on the basic principles of heat transfer,research is implemented on the method of the thermal conductivity error compensation with the fixed value of the immersed length of the thermocouple wire and the method of the radiation error compensation with the fixed value of relative change rate of the surrounding temperature.Simulation results of the quantitative relationship between the immersed length of the thermocouple,the relative change rate of the surrounding temperature,and temperature error are obtained.To evaluate the error mechanism analysis and simulation results,a wind tunnel validation test is carried out.Test results show that the measured thermocouple immersion error results are consistent with the theoretical simulation results,and the relative change rate of surrounding temperature ω<1 can significantly reduce the influence of temperature measurement radiation error,which can reduce the influence of temperature measurement radiation error on temperature uniformity by 7.12 times.The method presented in this article provides useful exploration and technical basis for the engineering application of the thermocouple in gas medium.

关 键 词：热电偶 导热误差 辐射误差 气流温度 

分 类 号：TH81[机械工程—仪器科学与技术] V211.71[机械工程—精密仪器及机械]