Summary

Abstract

The previous chapters focused on the topics related to the numerical solution of the Richards equation and on the development of upscaled forms of this equation suitable for binary porous media with inclusions. This chapter presents a summary of the most important points discussed earlier. It is emphasized that the commonly used schemes for inter-nodal permeability used in the numerical solution of the Richards equation may lead to significant errors, and that the choice of the appropriate scheme depends on the local balance of capillary and gravity forces for a single cell of the numerical grid. With regard to the problem of upscaling, it is stressed that the field-scale behaviour of a heterogeneous medium is heavily influenced, both qualitatively and quantitatively, by the relation between the capillary diffusivity coefficients and the air entry pressure values characterizing the two porous materials.