近岸浅海潮流数值模型及其应用

在Casulli提出的半隐式有限差分方法的基础上,通过改进底摩擦力公式以避免在超浅水域底摩擦项过大的缺点,对底摩擦项进行线性化处理以获得隐式效果,对平流项采用适当的差分格式以减小假扩散及对活动边界引入误差的传播,采用高效的选代格式提高运算速度,建立了适合于近岸浅海的潮流数值模型。该模型有良好的稳定性,计算时间步长不受CFL条件的限制。在防城港的潮流模拟中,模型的验证结果良好。

A NUMERICAL MODEL OF TIDAL CURRENT IN NEARSHORE SHALLOW SEA AND ITS APPLICATION

Based on the semi-implicit difference scheme presented by VincenzoCasulli, a numerical model suitable to current simulation of nearshore shallow sea isset up through improving the bottom friction formula to avoid excessively large valuesof bottom friction term at super shallow sea, linearizing the bottom friction term toget the effect of implicit treatment adopting proper difference scheme for theadvection term to decrease false diffusion and propagation of error resulted from the"movable boundary", and employing high effective iteration algothium to speed up thecomputation. The medel has good stability, the bine interval breaks through the CFLrestriction. In the process of curent simulation of the Fangcheng Harbor, the model isproved to be satisfactory.