Abstract:
A distributed mathematical model to simulate the overland flow from fallow upland phase of the small watershed subjected to rainfall conditions has been presented. Overland flow has been simulated using St.-Venant equations with kinematic wave approximation. Hein and Larson approach based on original Green and Ampt method has been used to estimate the rainfall excess rate. All the parameters of the model have physical significance and can be easily measured in the field or the laboratory by conducting experiments. The solutions to the governing partial differential equations of flow have been obtained using finite element technique and the model validated using reported runoff data.