Ｅ网格变量分布下差分格式的性质

本文用线性化的浅水波方程系统地分析、讨论了Ｅ网格变量分布下差分计算的性质；指出了目前有关讨论Ｅ网格差分性质在方法上存在的问题；给出了一种解决Ｅ网格中两个Ｃ网格分离的方法；提出了一种Ｅ网格用于海洋计算时，海洋侧边界条件的处理方法。初步的数值试验证明了这些方法对抑制Ｅ网格中的计算躁声是有效的。

Properties of the Spatial Finite-Difference Scheme Based on the E-Grid

By using the linearized shallow water equations, the properties of the spatial centered finite-differ-ence scheme based on E-grid are investigated systematically and some issues involving the E-grid are discussed in this paper.The E-grid may be considered as a superposition of two C-grid, and two solutions to gravity wave equations on these two C sub-grids may coekist independently, when the centered finite difference scheme is used on the E-grid. A special method which can solve this problem is persented in section 4.Because velocity and temperture variables exist always in any grid line for E-grid system, it is difficulty to propose proper lateral boundary conditions in the numerical models. A set of lateral boundary condi- tions suitable for rigid boundary, for example, the ocean boundary, is presented and disscussed in section 5. Some numerical experiments have demonstrated the feasibility of these methods.