Intense internal waves are common phenomena on mid-latitude continental shelves when the water column is stratified. In this paper, a nonlinear nonhydrostatic two-layer model is used to examine the details of the generation and evolution of these waves. This model indicates that the internal waves are generated by the interaction of the barotropie tide with the shelf break topography. The onshore flow of the tides causes an upward displacement of isopycnals. This disturbance splits into a pair of counter propagating waves. The subsequent offshore flow causes a downward displacement which acts in conjunction with advection to steepen the back face of the onshore propagating wave. Thus an internal onshore propagating shock is developed, which eventually disintegrates into a packet of solitary internal waves (SIW) through a process of nonlinear self-interaction. Meanwhile, the model results are compared with available experiment data.%内孤立波是陆架陆坡区一种常见的现象.借助于一个2层非静力近似模式(Gerkema)模拟分析了内孤立波在陆架生成及传播特性,并与已有的观测资料进行了比较分析.结果表明,正压潮与地形相互作用激发生成内潮,内潮在向岸传播过程中,由于正压潮流及自身的非线性作用而发生分裂,受频散作用的影响进一步演化成内孤立子波列.而对于离岸传播的内潮,由于较强的频散效应,非线性与频散在较大尺度上达到平衡,从而使得波形呈现椭圆余旋波的特征.
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