A finite volume scheme for simulation of rainwater harvesting process

Abstract

A finite volume scheme to numerically solve the twodimensional (2D) shallow water equations with source terms is presented. Innovative methods are developed for data reconstruction, flux splitting, evaluation of numerical fluxes, and treatment of source terms. Total variation diminishing (TVD) properties and monotonicity are established without using an approximate Riemann solver. The finite volume scheme is applied for numerical simulation of surface runoff phenomena in a watershed, which is the catchment area of a rainwater harvesting dam. The ground surface topography of the watershed is complex, and unsteady transcritical surface flow dominates the rainwater harvesting process. The simulation results demonstrate that the numerical model is excellent in terms of accuracy, robustness, efficiency, and applicability.