EFFECT OF THICKNESS RATIO ON MASS TRANSPORT BY INTERNAL WAVES PROPAGATING IN TWO-LAYER SYSTEM

抄録

The paper presents experimental and numerical investigations for understanding the mechanism of mass transport by internal wave propagation over a flat bottom in two-layer stratified fluid. The mass transport velocity has been estimated from the horizontal excursion of water particle. The water particle trajectories were obtained from PIV results in an experimental flume and also computed by a two-dimensional non-hydrostatic numerical model. We confirmed the numerical model reasonably reproduce the measured wave profile as well as the measured mass transport of the internal waves. A series of numerical experiments showed the dependency of mass transport on the layer thickness ratio and the wave height. We found that the maximum mass transport velocity is highest when the upper and lower layer thicknesses are equal and it becomes smaller as the thickness of lower layer exceeds that of the upper layer. For all thickness ratios, the mass transport velocity gets larger with increase of internal wave height.