Identification of parameters of Richards equation using Grey Wolf Optimizer algorithm

Abstract

In this paper, it is a question of identification of the parameters in the equation of Richards modelling the flow in unsaturated porous medium. The mixed formulation pressure head-moisture content has been used. The direct problem was solved by the finite difference method. The equation being strongly non-linear, we will use the  Picard's method. The function cost used is built by using the infiltration. The optimization method used is a meta-heuristic  called Grey Wolf Optimizer Algorithm (GWO). A test on experimental data has been carried. A comparison with genetic algorithm show that the GWO is a powerful algorithm for identifying parameters of the Richards equation.