2D Variably Saturated Flows: Physical Scaling and Bayesian Estimation

Abstract

A novel dimensionless formulation for water flow in two-dimensional variably saturated media is presented. It shows that scaling physical systems requires conservation of the ratio between capillary forces and gravity forces. A direct result of this finding is that for two physical systems to be hydraulically similar, the soil in the smaller system has to be coarser than the soil in the larger system. The new formulation is implemented in a finite-element model that compared favorably with published numerical results with a minimal mass balance error. Bayesian estimation using prior physical information was used to fit the model to experimental data that simulated tidal action in a laboratory beach. Results show that the model is not sensitive to the residual soil moisture or the parameter