Research in Calibration and Application Errors of Heat Flux Sensors

The influence of the presence of a built-in heat flux sensor on local heat flux has been studied.

Starting with the definition of a calibration value for the heat flux sensor (the intrinsic calibration value), this influence is described and expressed in measurement errors. The influence is considered to result from two separate and well-recognized effects, namely, the change in thermal resistance and the heat flux deflection. This splitting up has been proved correct by both experiments and calculations. A satisfying agreement between the methods was found.

The importance of a well-dimensioned guard ring, dependent on parameters such as thermal conductivity and dimension, is apparent. Finally, rough guidelines for the design of “low-error” heat flux sensors and a basic calibration method are given.