摘要
N-S方程数值模拟的精度和效率一直是计算流体力学的重要研究课题。结合欧拉-拉格朗日方法(ELM)和交替方向隐式方法(AD I)建立正交曲线坐标系二维浅水方程的ELAD I(Eu lerian-Lagrangian alternating d irection imp lic itm ethod)有限差分方法,详细阐述了基本原理和离散方法,分析了ELM方法的数值扩散特性,并通过室内水槽和天然河道资料与传统AD I方法进行了验证比较。模拟结果表明,ELAD I方法在达到一定计算精度的同时,计算效率显著提高,对于某些算例,比传统AD I方法提高近90%,Courant数可以达到40以上。
Accuracy and efficiency are two key factors for the numerical simulation of N-S equations in computational fluid dynamics.In this paper,the Eulerian-Lagrangian alternating direction implicit（ELADI） finite difference method for 2D shallow water equations in orthogonal curvilinear coordinate system is extensively discussed together with the basic principle and discretization methods.The ELADI method combines the alternating direction implicit method（ADI） with the Eulerian-Lagrangian Method（ELM）.The numerical diffusivity of the ELM method is analyzed.The ELADI method is compared with traditional methods using the laboratory experiments conducted in a curved flume,as well as field measurements from the Haoxue river bend in the upper Jingjiang Reach of the Yangtze River.The result shows that the ELADI method improves computational efficiency greatly with satisfactory accuracy.For the test case,ELADI even allows the Courant number reaching 40 and reducing the computational cost by 90% compared to the traditional method.
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2011年第4期523-531,共9页
Advances in Water Science
基金
水体污染控制与治理科技重大专项(2008ZX07526-005
2009ZX07528-003)~~
关键词
二维
正交曲线
浅水方程
欧拉-拉格朗日方法
交替方向隐式方法
2D
orthogonal curvilinear
shallow water equations
Eulerian-Lagrangian method
alternating direction implicit method
