This study is aimed to investigate, as a solitary wave propagating past a cavity; the motion of fluid particles inside a bottom cavity. A model formulated with stream function and vorticity is applied and the governing equations are solved using the finite-analytic method. In order to reveal the small eddy motion in a cavity, a boundary-fitted grid system combined with fine overset grids is adopted. The simulated motions of fluid particles at various times are shown to be similar to the experimental observations. The present model is demonstrated to be capable of capturing the motion of the fluid particles. Furthermore, the effect of incident wave height on the patterns of fluid-particle motion and the removal displacement along the vertical and horizontal directions are analyzed and the results are presented and discussed.
Wave induced current as it passes over an uneven bottom (natural topography or artificial structures) tends to deform the free surface and generate vortices in the regions with changing water depth. This study focuses on modeling the propagation of an incident solitary wave past a rectangular cavity (trench). The kinematic motions of the particles within a cavity is also investigated. The easy deposition of materials into the cavities can be a major concern. Numerous studies of flow over cavities without a free surface have been motivated by a fundamental interest in the phenomenon of separated flow. For examples, in the processing industry, the residues of industrial manufacturing processes can give rise to an accumulation of deposits in cavities of rough surfaces and consequently a corresponding degradation of quality in the processed material may be observed (Fang et al. 2003). In aerodynamics when a shock wave passes a cavity, the ascent of the particles (e.g. dusts) in the cavity leads to a gas-particle mixture problem (Bedarev et al., 2007).