On the measurement of the in-plane thermal diffusivity: Data analysis in thin foils experiments

The thermal diffusivity of materials is a key parameter to evaluate the thermal behavior of industrial components. Several methods are available to estimate the diffusivity, using different measurement techniques. Amongst them, recently a photothermal technique has been developed for the case of thin foils. This work further investigates some analytical solutions of the two-dimensional heat conduction differential equation for the geometry of a thin foil. The foil is made of a homogeneous material and is so thin that variations in temperature across it are negligible. On the contrary, on the surface of the foil, the temperature variation can be made considerable by delivering a localized heat pulse. It can be captured by a sequence of IR images. The model is then applied to some photothermal experimental setups. The analysis of thermal data leads to the estimation of the thermal diffusivity. In this work, the postprocessing technique is discussed, with a focus on the challenges of error analysis.The analysis of thermal data leads to the estimation of the thermal diffusivity. In this work, the postprocessing technique is discussed, with a focus on the challenges of error analysis.