Simultaneous identification of thermal diffusivity, thickness, and heating center point based on surface temperature variation excited by laser-spot heating

An infrared thermographic technique was developed for identifying the thermal diffu-10sivity from temperature variation data of specimen surface. A laser-spot heating is applied to the11specimen surface for a certain period and then temperature variation of the surface is measured12using infrared thermography. Since analytical solution for the temperature variation is expressed13in terms of parameters including the thermal diffusivity,thickness and heating pointposition,the14parametersare identifiedby fitting theanalytical solution to the measured data. The developed15technique was applied to a ceramic specimen for verification. It was shown that the thermal diffu-16sivity can be identified with high accuracyif the thickness and heating pointpositionare known17in advance. Furthermore, it is confirmed thatthe thermal diffusivity, thickness, and heating point18positioncan be simultaneously estimated with acceptable accuracy.