潮流数值模拟中动边界处理方法研究

论文提出了一种新的干湿判断方法来处理潮流数值模拟中潮间带上的动边界问题。文中的干湿判断方法主要是通过显式求解所得的“预估水深”和流速方向确定单元边的干湿状态。干湿判断过程中不仅考虑到水位对干湿状态的影响，而且包含了流速、流向和风应力等因素；判断过程不必分成“干”判断和“湿”判断两步进行。对三个测试算例进行了干湿判断模拟，模拟结果显示：干湿判断方法无明显的数值振荡，模拟结果的水面光滑；可以较准确的估计浅水处水体的蓄留能力，能保证干单元的水深均小于门限水深且为有限的正值；可以较准确的模拟潮间带上的动边界问题。

The study on simulation of moving boundary in numerical tidal flow model

A new wetting and drying method for the numerical tidal flow model is developed to deal with the moving boundary due to tidal waves at the tidal flat.In the new method a "predicted water depth" is solved explicitly and is used to determine the moving boundary in combination with the direction of tidal flow.In the new method,besides the water elevation,more factors such as the speed and direction of tidal flow and wind shear stress are taken into account;the procedures of the new method are undertaken by similar checks at every half time step instead of the divided drying checks and wetting checks.In order to validate the new method,three test cases were performed.The results show that the new method leads to no excessive numerical wiggles and results in so effective estimation of retention volume in each cell that the depth of every dry cell is a finite positive value and less than the threshold,and that the method can be used to simulate the moving boundary at the tidal flat exactly.