Tratamiento del frente abrupto de infiltración para el caso de profundidad de inundación variable. Soluciones implícita y explícita

Abstract

The “sharp wetting front” infiltration model has been developed forconditions of decreasing ponding depth in an isolated system. The implicit dimensionless equations obtained relate the infiltration rate and the flooding depth to time. By defining dimensionless variables of flooding depthsand time xthe equation ds/dxwas obtained, which is a function of only onedescriptive parameter; in it, all the variables describing the initial dynamic conditionsare included.This parameter determines the shape of the curve given by the dimensionless infiltration equation combining the variables sand x. Afterwards a parametric explicit expression s(x)depending onone parameter ahas been obtained; ain turn depends on and has four generic constant coefficients valid for a wide range of physical soil properties and conditions occurring in nature. By means of numeric simulations using a wide range of values for the soil parameters and different initial flooding depths, it is proved that the proposed explicit parametric function generates similar infiltration rates and cumulative storages to those that are obtained starting from Darcy’s equation in the extended Green-Ampt scheme.