In the research of aerospace engine technology, accurate measurement of airflow temperature in high temperature and high speed environment is usually required to evaluate the performance of the engine. In addition, depth of the thermocouples insertion at high temperature airflow is very short due to the restriction of geometrical space and sensor strength, which causes large thermal conductivity error and affects the judgment of engine working characteristics. In this paper, research on thermal conductivity error of short type thermocouple is carried out. A simulation model of thermal conductivity error for short thermocouple is established. And the accuracy of the simulation model is verified further. Through numerical simulation, the influence of thermocouple insertion depth, Mach number of incoming flow, total temperature of incoming flow and substrate temperature on the correction coefficient of heat conduction error was studied. The response surface model of thermal conductivity error correction coefficient was established. The simulation results can provide an idea for the suppression of thermal conductivity error of short thermocouple and provide a support for the measured data correction in the application process of thermocouple.%在航空航天发动机技术的研究过程中, 通常需要准确测量高温、高速环境下的气流温度以衡量发动机的性能, 由于传感器强度等因素的限制, 温度传感器插入高温气流深度较小, 造成很大的导热误差, 影响发动机工作特性的评判.对此专门开展了短型热电偶温度传感器导热误差的研究, 建立相应的短型热电偶导热误差仿真模型, 并进一步验证了仿真模型的准确性.在此基础上通过仿真手段研究不同热电偶插入深度、不同来流马赫数、不同来流总温和不同基底温度对导热误差修正系数的影响规律, 并建立了热电偶导热误差修正系数的响应面模型.仿真研究结果可以为短型热电偶导热误差的抑制提供思路并为热电偶使用过程中测量数据的修正提供支持.
展开▼
