0000000000206987
AUTHOR
Vijay P. Singh
Multiple Non-linear Reservoirs to Model Water Balance Components in Sandy Soils
In the hydrologic literature, to model water flow in unsaturated soils, the Richards equation is usually applied, allowing the main components of the hydrologic cycle, as rainfall partitioning into surface runoff and infiltration, to be determined. The Richards equation is highly nonlinear, making very challenging to derive analytical solutions. Recently, for constant rainfall intensity, under the simplified hypothesis of gravity-driven infiltration, and by assuming a capacitance framework, a simplified solution of the Richards equation that considers the Brooks and Corey hydraulic conductivity function was suggested. By maintaining the assumption that the infiltration process is dominated …
Modeling the probability distribution of peak discharge for infiltrating hillslopes
Hillslope response plays a fundamental role in the prediction of peak discharge at the basin outlet. The peak discharge for the critical duration of rainfall and its probability distribution are needed for designing urban infrastructure facilities. This study derives the probability distribution, denoted as GABS model, by coupling three models: (1) the Green-Ampt model for computing infiltration, (2) the kinematic wave model for computing discharge hydrograph from the hillslope, and (3) the intensity-duration-frequency (IDF) model for computing design rainfall intensity. The Hortonian mechanism for runoff generation is employed for computing the surface runoff hydrograph. Since the antecede…
Analytical solution of kinematic wave time of concentration for overland flow under green-ampt infiltration
In this paper the well-known kinematic wave equation for computing the time of concentration for impervious surfaces has been extended to the case of pervious hillslopes, accounting for infiltration. An analytical solution for the time of concentration for overland flow on a rectangular plane surface is derived using the kinematic wave equation under the Green-Ampt infiltration. The relative time of concentration is defined as the ratio between the time of concentration of an infiltrating plane and the soil sorptivity time scale, depending on the normalized rainfall intensity and a parameter synthesizing the soil and hillslope characteristics. It is shown that for a more complex case (corre…
Overland Flow Times of Concentration for Hillslopes of Complex Topography
The time of concentration is an important parameter for predicting peak discharge at the basin outlet and for designing urban infrastructure facilities. In studying the hillslope response, employing hydraulic equations of flow, the shape of the hillslope geometry has often been assumed as rectangular and planar. However, natural hillslopes have complex topographies whose shapes are characterized by irregularly spaced contour lines. Recently, kinematic wave time of concentration has been derived for rectangular and curved parallel hillslopes. This paper extends this work to hillslopes of complex planform geometry, considering the degree of divergence or convergence of the hillslope. The exte…