SIMULATION OF BORDER IRRIGATION SYSTEM USING EXPLICIT MACCORMACK FINITE-DIFFERENCE METHOD

The hydrodynamic, zero-inertia and kinematic wave models for simulatin g all phases of the border irrigation event are presented. The explici t second-order accurate MacCormack method is used for solving the gove rning equations. A technique for implementing the boundary conditions that are consistent with the numerical scheme is discussed. All the th ree models do not require a special treatment such as moving grid, def ormable grid, subgrid technique, etc., to accurately simulate the adva ncing and receding fronts. The results of all the three models namely hydrodynamic finite difference model (HDFD), zero-inertia finite diffe rence model (ZIFD) and kinematic wave finite difference model (KWFD) a re compared with observed advance and recession times for four border irrigation events available in literature. A very good comparison of r esults is observed, The relative merits and demerits of the models are discussed. The HDFD model is found to be more suitable for simulation of all the four phases of border irrigation events. (C) 1998 Elsevier Science B.V.