非恒定水深平均的K－ε紊流模型的有限元模式

Finite Element Method of Unsteady Depth-averaged K-ε Turbulence Model in Open Channels

本文在水深平均的二维流动的数学模型基础上，引入Ｋ－ε二方程模式，建立了水深平均的Ｋ－ε紊流模型，采用能适应不规则边界的有限元计算模式，对易引起不稳定的对流项引进迎流技巧，从而大大提高了计算稳定性。针对应用到河口海湾中的紊流模型具有大尺度计算网格的特点，本文分析了常用壁面律的局限性，比较了Ｋ方程中ＧＫ项与ＧＫＶ项的大小，并分析了紊流模型的优点。

Depth-averaged K -ε turbulence model is established in this paper. In order to deal with irregular boundaries in estuaries, explict FEM is used with triangle elementS and upstream technique in convective terms whiCh can improve computational stability. This turbulence model has been applied in Jiaojiang Estuary. Considering large computational region in estuaries, this paper also analyses the fault of common K and ε wall boundary, compares the effect of Gk and Gkv in K equation,and illustrated the advantages of turbulence model.