Spectral stochastic modeling of uncertainties in nonlinear diffusion problems of moisture transfer in wood

The main purpose of this paper is to demonstrate that the stochastic spectral method based on polynomial chaos expansion can be more efficient in modeling uncertainties associated with moisture transfer in wood than Monte Carlo method mainly when considering a small number of random variables. This spectral approach has a big advantage over the Monte Carlo method (statistical approach) in terms of computer time. Numerical example of diffusion of moisture in convective drying of wood is given and there is shown that the results (mean and the standard deviation) obtained with the stochastic spectral method are in good agreement with the results of the Monte Carlo simulations.