A numerical model to simulate overland water flow applied to surface irrigation systems

摘要

In this study, an overland water flow model is presented and applied to simulate water flow in several field experiments in surface irrigation systems. The well-known Saint-Venant equations (as the governing equations) were discretized using a control volume of moving cells and the discretized equations were linearized by applying a Taylor series expansion according to the Newton-Raphson procedure. Then, applying the Gaussian elimination technique iteratively solved the obtained algebraic linearized equations. The model was then applied to simulate several experimental data over a wide range of field conditions. The results showed that the model was able to predict overland water flow parameters in surface irrigation systems (e.g. advance and recession times, infiltrated water) reasonable well. However, the model overestimated runoff water at the end of the field because of steady state assumptions at the outlet boundary condition.