Asymptotic solutions for sorption of water by a heavy clay soil
1997
Emerman, S.H.
Heavy clay soils are characterized by a strong power-law dependence of the soil water potential on the soil water content. Numerical solutions for water transport are difficult for such soils so that analytical solutions become crucial. Asymptotic solutions are derived for the sorption of water by an initially dry, heavy clay soil which are valid in the limit of large power-law exponent, as defined by the Campbell relation. The most general boundary condition considered is surface flux as a powerlaw function of time with arbitrary exponent. A new exact solution is also derived for the Richards equation which is valid for a particular time-dependence of the surface flux. It is shown that a previous asymptotic solution in another context is a special case of the solutions of this paper.
显示更多 [+] 显示较少 [-]