在海洋内波多发区, 海底地形变化是影响海洋内波生成、传播和演化的重要因素。本文基于不可压缩原始N-S方程, 在非静压近似条件下, 通过建立适应于非线性海洋内波研究的非静压海洋动力学模型, 并将其应用于正压潮驱动下的内孤立波生成和传播的数值模拟研究。根据模拟结果, 研究了一类单海脊地形拓扑结构变化对内孤立波生成和传播的影响; 分析并讨论了地形拓扑结构参数变化与生成的内孤立波传播至特定位置的抵达时间、强度等特征参数之间的变化关系; 提出内孤立波生成之前在海脊一侧形成“L-下陷”结构的观点, 并揭示了与该观点相合的能量“积聚”和“释放”机制。
In regions of internal waves, topography is commonly an important factor for internal waves’ generation, propagation and evolution. Based on incompressible primitive Navier-Stokes equations, a non-hydrostatic oceanic hydrodynamics model is employed to study internal solitary waves (ISWs). Generation and evolution processes of nonlinear internal waves are simulated in the numerical model forced by barotropic tide. Using the simulation results, topological structure changes of single-ridge terrain on the generation and propagation of solitary waves are presented. According to the simulations of various topographic depths and extended parameters, analysis is done in terms of arrival time and intensity of ISWs. Following that, an “L-depression” structure would appear on the opposite side of the ridge before ISW generation is proposed, and a -“accumulation” and “releasing” mechanism on energy with the “L-depression” structure is also indicated.
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