抛泥扩散淤积分布计算

Simulation of diffusion and siltation caused by dumped sediment

在平面二维潮流场的基础上,采用欧拉———拉格郎日质点漂移法对抛泥扩散淤积分布进行模拟计算。该方法不需要求解大型方程组,仅用有限个质点代表抛泥产生的污水团,根据单个质点所在地的已知流速、流向、水深、含沙量等参数,以及当地的其它自然条件,选择某个合适简便的泥沙公式,就能模拟污水团运移过程中泥沙造成的淤积范围和淤积厚度。通过对长江口北槽拟选倾倒区抛泥的淤积情况进行模拟计算,结果与示踪沙试验基本吻合,说明该方法对抛泥淤积的计算是可行的。

Based on the two - dimensional tidal flow fields, the paper simulates the diffusion and siltation distribution due to dumped sediment by the means of Euler - lagarange particle drift. Instead of solving large - size equations, the method makes use of several particles to represent＂ sewage mass＂ caused by dumped sediment, and according to the parameters as the local velocity, direction,water depth and sediment concentration at the spot of the single particle and the other local natural situation, then the silt range and thickness caused by sediment in the transportation of ＂sewage mass＂ could be simulated by suitable and simple sediment equation. On the basis of simulation of the silt condition of the sediment throw in the planed throw area located at the north channel of Yangtze River estuary, the result is agreed with the outcome of trace - sand experiment. It is proved that the method put up with the paper is reasonable.