A nonhydrostatic numerical model was developed and numerical experiments performed on the interaction of an internal solitary wave （ISW） with a sill, for a two-layer fluid with a diffusive interface. Based on the bl...A nonhydrostatic numerical model was developed and numerical experiments performed on the interaction of an internal solitary wave （ISW） with a sill, for a two-layer fluid with a diffusive interface. Based on the blocking parameter （Br）, the flow was classified into three cases： （1） when bottom topography has little influence on the propagation and spatial structure of the ISW （Br〈0.5）, （2） where the ISW is distorted significantly by the blocking effect of the topography （though no wave breaking occurs, （0.5〈Br〈0.7）, and （3） where the ISW is broken as it encounters and passes over the bottom topography （0.7〈Br）. The numerical results obtained here are consistent with those obtained in laboratory experiments. The breaking process of the incident ISW when Br=0.7 was completely reproduced. Dissipation rate was linearly related to the blocking parameter when B,〈0.7, and the maximum dissipation rate could reach about 34% as Br raised to about 1.0. After that, instead of breaking, more reflection happened. Similarly, breaking induced mixing was also most effective during Br around 1.0, and can be up to 0.16.展开更多
基金The National Natural Science Foundation of China under contract Nos 41528601 and 41376029the Youth Innovation Promotion Association of Chinese Academy of Sciences under contract No.Y4KY07103Lthe Strategic Priority Research Program of the Chinese Academy of Sciences under contract No.XDA11020101
文摘A nonhydrostatic numerical model was developed and numerical experiments performed on the interaction of an internal solitary wave （ISW） with a sill, for a two-layer fluid with a diffusive interface. Based on the blocking parameter （Br）, the flow was classified into three cases： （1） when bottom topography has little influence on the propagation and spatial structure of the ISW （Br〈0.5）, （2） where the ISW is distorted significantly by the blocking effect of the topography （though no wave breaking occurs, （0.5〈Br〈0.7）, and （3） where the ISW is broken as it encounters and passes over the bottom topography （0.7〈Br）. The numerical results obtained here are consistent with those obtained in laboratory experiments. The breaking process of the incident ISW when Br=0.7 was completely reproduced. Dissipation rate was linearly related to the blocking parameter when B,〈0.7, and the maximum dissipation rate could reach about 34% as Br raised to about 1.0. After that, instead of breaking, more reflection happened. Similarly, breaking induced mixing was also most effective during Br around 1.0, and can be up to 0.16.
