Dual Reciprocity Boundary Element Method-based analysis of infiltration in heterogeneous soils under different irrigation channel types

Abstract

The research discussed analysis of infiltration in heterogeneous soils under different irrigation channel types. The heterogenous soils consist of layer 1 is silt loam (SL) and layer 2 is pima clay loam (PCL). Irrigation channel types that discussed consist of trapezoidal, rectangular, semi-circular, triangular, impermeable based of trapezoidal , and impermeable based of rectangular channel. The problem is governed as Richards' equation converted into a modified Helmholtz equation to serve as a mathematical model. This model is then solved numerically using the Dual Reciprocity Boundary Element Method (DRBEM). The resulting numerical solution is the suction potential in each type of irrigation channels. The area below of the channels with the highest suction potential value are the irrigation channels without impermeable. In irrigation channels with impermeable based, the area below of the channels has a low suction potential value. The solution also indicate that there are jumps of suction potential value from layer 1 to layer 2. The order of highest to lowest suction potential values obtained from the solution are triangular, rectangular, semi-circular, impermeable based of trapezoidal, and impermeable based of rectangular channel