Abstract
The state of heat loss from combustion gas to combustion chamber walls in an internal combustion engine can be evaluated from instantaneous surface temperature of the walls measured by thin-film thermocouples. For this purpose, measurement devices should ensure high accuracy and synchronize with the engine operation. On the other hand, the measurement circuit used needs to be noise-free and quick in response. Furthermore, meaningfully reproductive data must be generated from the data processing device. In this report, the authors' measurement system including all those devices is presented.