Multiscale method for estimating the thermal properties of thick multilayers using infrared thermography

Overview & Synopsis

Characterizing the thermal properties of thick materials remains complex due to the long-time scales required to probe deep diffusion. We propose combining flash and step thermography methods with analytical modeling based on the quadrupole method, which allows the thermal response to be reproduced over large time windows. This approach facilitates the identification of the thermophysical parameters of each layer. The method is applied to two multilayer materials: an aluminum-cork system and a more complex flax-cork sandwich, impacted at different temperatures. The results demonstrate the ability of this joint strategy to improve the accuracy of the estimation of the characteristics of the different layers and to better describe heat diffusion in thick structures.