[AHW33-06] Linking micro scale hillslope properties and a meso scale constitutive equation used in rainfall-runoff modeling
★Invited Papers
Keywords:hillslope properties, constitutive equation, water flows, coupled model simulations
A number of rainfall-runoff models have been developed in the field of hydraulic and hydrologic engineering, with a special emphasis on simulating temporal patterns of river discharge in order to meet practical demands such as discharge predictions. Conceptual rainfall-runoff models were initially developed, followed by physical-based models. The physical-based models have achieved a certain level of success, which was partly due to the rapid advancement of computers and the increasing availability of a variety of datasets. It is pointed out, however, that recent important findings based on field studies are not incorporated into rainfall-runoff models, especially used for engineering purposes. To examine the raised issue, this study conducted detailed simulations coupling surface flow, saturated-unsaturated flow and pipe flow for hillslope rainfall-runoff processes, and investigated the validity of a constitutive equation (depth-discharge relationship) used in a rainfall-runoff model. The results revealed that the constitutive equation was capable of describing the dynamics of water flows arising on a steep hillslope with relatively wet conditions.