摘要
针对当前复杂环境水流模拟的需求,建立了新型的基于特征型高分辨率数值算法的三维非结构网格浅水动力模型。模型采用有限体积法离散sigma坐标下的三维浅水方程,运用Roe黎曼近似解评估水平界面通量。模型网格拟合边界能力强,可根据需要局部加密;格式数值性能优良,具有守恒性、单调迎风性、高数值分辨率等特性。同时,应用干湿判别法处理动边界,以适应浅滩地形漫/露过程模拟的需要。封闭水池内部风生环流、干河床上溃坝过程和长江口实际潮流场的模拟从不同侧面展示了模型的特点,结果表明它能够准确地预测水流的三维流动结构,而且计算简单高效,具有良好的数值稳定性。
A new efficient characteristic-based numerical model for 3-D shallow water is presented and discussed in this paper. The model is based on the collocated, finite volume method with unstructured grids. One attractive feature of the model is that it has ability to handle arbitrary topology. The other is that horizontal mass and momentum flux across interface of cells is calculated by the Roe＇s Riemann approximation solver and the monotone, conservation scheme make a simulation results for keeping water balance in the entire computational field. The wetting-drying algorithm is also proposed to simulate flooding processes in sand shoal. To validate the model, the numerical simulation is performed for three cases： the wind driven circular flow, the dam-break wave on initial dry bed and the tidal flow in estuary of the Yangtze River. Results show that the model can accurately simulate the 3-D flow structure, and has good numerical stability.
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2006年第5期693-699,共7页
Advances in Water Science
基金
中国科学院知识创新工程方向性项目(KXCX3-SW-331)
中国科学院南京地理与湖泊研究所所长专项基金(s250019)联合资助~~
关键词
三维
浅水
非结构网格
黎曼近似解
sigma坐标
动边界
水动力模型
3-D numerical model
shallow water
unstructured grids
Riemann approximate solver
sigma coordinate transformation, moving boundary
hydrodynamic model
