Abstract
It has been investigated that an open-channel flow with a relatively large-scale side cavity exhibits water surface oscillations in spanwise or streamwise directions. Such oscillations, once occurred in actual river installing a side cavity zone as a water-friendly facilities in the urban areas, may cause flooding, resulting in a large damage in the residential area. In order to investigate the flow features associated with such surface oscillation, the authors have developed a 3D LES model that utilizes a density function for detecting air-water interface. With the developed model, it becomes possible to simulate time-dependent water surface variation with a reasonable accuracy as compared with the experiments. In this paper, local flow features along the interface between main channel and side cavity zone are investigated by distributing virtual tracers following the 3D flow pattern.
