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运用高分辨率的边界适应网格进行流体动力学数值计算时，如何提高计算稳定性和减少计算量成为数值求解的关键性问题。在非正交的边界适应坐标系中，每个动量方程中同时出现了两个交叉方向的水位偏导数项，给隐式求解带来困难，而显式格式下的时间步长由于受与空间步长有关的Ｃｏｕｒａｎｔ－Ｆｒｉｅｄｒｉｃｈｓ－Ｌｅｗｙ条件限制，计算量成倍增加．本文从广义曲线坐标系下浅海动力学方程组出发，导出了流速的逆变张量所满足的动量方程组，使方程中的水位偏导数项变成了沿某一协变基向量方向占优的形式，方便地采用了交替方向隐式差分格式，从而提高了计算稳定性并减小了计算量。本文通过对澳门海域航道和港池中流场的计算，证实了该模式是一种进行高分辩率数值计算的有效方法。
When using the high-resolution boundary adaptive grid to calculate the hydrodynamics, how to improve the computational stability and reduce the computational cost become the key problems in numerical solution. In the non-orthogonal boundary-adaptive coordinate system, the partial derivative of water level in two cross directions appears in each momentum equation, which imposes difficulties on implicit solution. However, the time step in explicit format due to space-time Courant-Friedrichs-Lewy constraints related to step size, the amount of computation multiplied. In this paper, starting from the shallow-sea dynamic equations in a generalized curvilinear coordinate system, the momentum equations satisfied by the inverse tensors of the flow velocities are derived. The partial derivative of the water level in the equation becomes dominated by the direction of a covariant vector , The alternating direction implicit difference scheme is adopted conveniently, which improves the computational stability and reduces the computational complexity. In this paper, the calculation of the flow field in the channel and the basin in the sea of Macao shows that the model is an effective method for numerical calculation of high resolution.