Analytical solutions to runoff on hillslopes with curvature: numerical and laboratory verification

Autor: Sally E. Thompson, Cy David, Dana Ariel Lapides, Anneliese Sytsma, David N. Dralle
Rok vydání: 2020
Předmět:
Zdroj: Hydrological Processes. 34:4640-4659
ISSN: 1099-1085
0885-6087
Popis: Predicting the behavior of overland flow with analytical solutions to the kinematic wave equation is appealing due to its relative ease of implementation. Such simple solutions, however, have largely been constrained to applications on simple planar hillslopes. This study presents analytical solutions to the kinematic wave equation for hillslopes with modest topographic curvature that causes divergence or convergence of runoff flowpaths. The solution averages flow depths along changing hillslope contours whose lengths vary according hillslope width function, and results in a one‐dimensional approximation to the two‐dimensional flow field. The solutions are tested against both two‐dimensional numerical solutions to the kinematic wave equation (in ParFlow) and against experiments that use rainfall simulation on machined hillslopes with defined curvature properties. Excellent agreement between numerical, experimental and analytical solutions is found for hillslopes with mild to moderate curvature. The solutions show that curvature drives large changes in maximum flow rate q peak and time of concentration t c , predictions frequently used in engineering hydrologic design and analysis.
Databáze: OpenAIRE