Instantaneous Surface Temperature Measurement in Internal Combustion Engine Using Newly Developed Coaxial Type Thin-Film Temperature Sensor

In order to establish standard method to evaluate cooling loss in combustion chamber of internal combustion engines based on measurement of instantaneous heat flux / wall temperature with higher response and accuracy than previously reported coaxial type thin-film temperature sensor by applying thin film fabrication technology based on PVD method (Physical Vapor Deposition method) which improved to realize higher responsiveness than the conventional sensor was developed by the authors, and it was confirmed that the sensor has sufficient durability in conditions in which the hydrogen jet and flame directly contacts surface of the sensor by thin-film material change. The influence of the improvement on the measurement accuracy was verified by numerical analysis including thermoproperty evaluation. In this report, the configuration of measurement system that can measure minute voltage from the sensor with low noise and high response is reported. Furthermore, in addition to the thermoelectromotive force calibration, an instantaneous responsiveness evaluation device (laser calibration device) that can evaluate the responsiveness of instantaneous heat flux of the sensor was developed and evaluated.