IMPLEMENTATION OF DUAL RECIPROCITY BOUNDARY ELEMENT METHOD TO SOLVE THE MATHEMATICAL MODEL OF STEADY INFILTRATION IN HETEROGENEOUS SOILS VERTICALLY Armando Deminto Paa, Imam Solekhudin
Department of Mathemathics, Universitas Gadjah Mada
Abstract
The Dual Reciprocity Boundary Element Method (DRBEM) is applied to the Richard^s equation for steady infiltration in unsaturated soil. The types of soil observed are Guelph Loam (GL) and Pima Clay Loam (PCL). This study observes infiltration in vertically heterogeneous soil. A mathematical model for infiltration in heterogeneous unsaturated soil is built using the Richard^s equation and the Gardner model, with soil parameters provided by GL and PCL. The observed heterogeneous soil types include GL-PCL and PCL-GL. The numerical simulation results provide the hydraulic conductivity values for each type of soil. Based on the numerical results of the hydraulic conductivity, the soil water potential values can be calculated using the Gardner model. Observations regarding the hydraulic conductivity and soil water potential values obtained from both homogeneous and heterogeneous soil are conducted in this study.
Keywords: Richard^s equation, Gardner^s model, Hydraulic conductivity, Soil water potential
