Thermal diffusivity measurements of spherical samples using active infrared thermography

This work presents a method for measuring the thermal diffusivity of spherical samples using active infrared thermography. The principal novelty of this method lies in the deduction of an analytical model to obtain the spatial and temporal distribution of temperature in spherical samples. The model is obtained from the classical theory of heat conduction or the 3D heat diffusion equation. In order to analyze the behavior of the model, an active infrared thermography is used in order to monitor the spatial and temporal temperature distribution. Three different materials are used as spherical samples and they are heated by radiation increasing this way its temperature. The recorded data is fitted to the model by adjusting the diffusivity parameter. The results of the diffusivity values obtained using this model are consistent with those obtained from a standard thermal properties analyzer.