Non-Fickian diffusion in biosourced materials: Experimental determination of the memory function using minute samples

Abstract

Focusing on non-Fickian diffusion in biosourced materials, we have recently developed a new formulation that can model this behavior using memory functions. To identify those memory functions, an experimental device based on a magnetic suspension balance is used. Very thin samples of low-density fiberboard, medium-density fiberboard, and Spruce in the longitudinal direction are subjected to variations in ambient relative humidity (RH) while their mass is recorded. The imposed RH and temperature are used as boundary conditions in a comprehensive model to solve the heat and mass transfer equations in porous media. A computational code solving the new formulation was used to determine the memory functions by inverse analysis. The use of very thin samples enables macroscopic parameters to be considered as negligible compared to microscopic effects.