Estimation of an effective water diffusion coefficient during infrared‐convective drying of a polymer solution

This article deals with the drying of an aqueous solution of polyvinyl alcohol mixed with a plasticizer. A heating combining forced convection and short‐infrared radiation was investigated. A one‐dimensional model taking into account the shrinkage of the product was developed to get the temperature and moisture content evolutions during the drying. The water diffusion coefficient was estimated by an inverse method. A sensitivity analysis and numerical tests showed the relevance of using an objective function taking both mass and temperature measurements into account for the estimation procedure. This estimation was performed on several convective and infrared‐convective experimental drying kinetics. The model predictions fit well mass and temperature experimental data.