A novel step-integration method for thermal diffusivity measurement by means of converging thermal wave technique

A new step-integration method for thermal diffusivity measurements in thin sheet materials by the converging thermal wave technique is considered. This method is based on an integration of the temperature evolution curve with respect to the current time during two consecutive intervals of time, the duration of the first one being set beforehand and the completion time of the second one being obtained from the equality of the first and the second integrals. The use of the integrating operations with the following equalization of the integrals minimizes errors caused by heat loss and signal noise while the error due to the pulse duration is negligible, since a part of the experimental temperature evolution curve is properly taken. This method is of importance to develop an automated system for thermal diffusivity measurement