嵌套叉树网格的FDS数值模式在近海水域污染混合区计算中的应用

鉴于海域覆盖面积大而污水排放形成混合区相对集中的特点,基于四叉树网格布设的思想,分层次对不同研究区域按不同尺度网格对近海水域进行嵌套网格联合布置,重点模拟污水排放形成的混合区范围,在此基础上建立了Godunov型通量差分裂(FDS)格式有限体积法计算模式,实现了在不同尺寸的网格联立求解,提高了数值计算效率,又保证了计算精度.以海州湾近海水域为例,对海州湾近海水域流场及污染物混合区的范围进行了模拟计算,由此建立了排污量与混合区面积之间的响应关系,为环境管理部门对入海排污量的总量控制提供了依据.

Application of the nested adaptive quadtree grids FDS numerical model to the pollution zone for inshore water region

Currently the costal water pollution problem is more serious with the increase of waste discharge into inshore region. According to the characteristics of inshore regions with large scale of area,the rational grids distribution construction is important to improve computational enfficiency and precision for inshore regions. Based on the idea of the quadtree grid structure, the nested adaptive quadtree grids for the inshore water region is distributed according to demand of different research areas in this paper. The grid is densified scattered in the coastal pollution region,and the pollutant zone is focused to simulate. A numerical model is established by using the flux difference splitting(FDS)scheme of Godunov-type,and applied to simulation of flow and concentration fields for Haizhou Bay.Then the relationship curve between the waste discharge amount and the area of pollution zone is gained under the given condition of tidal range. The pollution control plan for cutting down waste discharge amount are obtained according to the limit area of pollution zone by environment protection department.