Efficient Simulation of Surface Water Flow in 2D Basin Irrigation Using Zero-Inertia Equations

Zero-inertia equations are more easily numerically solved than complete hydrodynamic equations. Thus, the zero-inertia equations were applied to describe the surface water flows in 2D basin irrigation. Then, finite-volume and finite-difference approaches in the spatial cell and cell interface spatially were applied to discretize the continuous and momentum components of zero-inertia equations, respectively. Meanwhile, a dual time-stepping approach was implicitly implemented to achieve unconditional stability. The Gauss-Seidel iterative method was used to solve the space-time discretized expressions of the zero-inertia equations, and an efficient numerical model for 2D basin irrigation was developed. Three field experiments were conducted to validate the developed model. The validated results show that the developed model presents good agreement between the simulated and observed data, and achieves more mass conservation than the existing model. Its high efficiency is suitable for practical engineering. (C) 2016 American Society of Civil Engineers.