| Thin-film thermocouple has good spatial and temporal resolution,can meet the need of measuring transient temperature and the temperature of small space size.Therefore,in the field of the industrial manufacturing,aerospace and chemical safety,it has become more and more widely used.With the increase demand of the transient temperature measurement in various industries,accurate evaluation of the thin-film thermocouple dynamic characteristics puts forward higher requirement.However,most of the research and application are mainly experimental measurement,the existing theory achievement cannot fully describe the factors that influence the dynamic performance measurement.The thin-film thermocouple dynamic calibration method has yet to establish a unified approach,there exists a larger measurement error.So the thin-film thermocouple dynamic characteristics analysis from the heat transfer mechanism has become a critical step to further improve the performance of the sensor.In order to solve the lack of theoretical basis on thin-film thermocouple dynamic characteristics evaluation method,this dissertation analyses the heat transfer phenomena involved in the thin-film thermocouple dynamic calibration,the concrete content includes the following two aspects:Firstly,it explored the heat transfer problem in the thin-film thermocouple dynamic characteristics calibration by oil bath step method and laser pulse method,and established the heat transfer model,achieved the thin-film thermocouple dynamic characteristics parameters of the theoretical value and analyzed its influencing factors by using the finite element simulation.Secondly,verified this theory analysis through the dynamic calibration experiments,compared the two dynamic calibration methods of thin-film thermocouple dynamic response,analyzed the defects and disadvantages of the existing calibration methods,and proposed the ideal conditions that conform to the thin-film thermocouple dynamic calibration according to the analysis results.In this dissertation,the heat transfer of the thin-film thermocouple dynamic calibration is analyzed,in order to provide the guidance to establish a reasonable thin-film thermocouple dynamic calibration method,it has an important guiding significance to improve the performance of thin-film thermocouple and expand its application field. |
