05-21天元基金几何与随机分析及其应用交叉讲座之157【Yang Yang】

发布者:系统管理员发布时间:2019-05-17浏览次数:126

题目:Local discontinuous Galerkin method for convection-diffusion equations on overlapping meshes
报告人:Yang Yang(Michigan Technological University)
时间: 2019年5月21日(周二)上午10:15-11:15
地点: 管理科研楼 1208

摘要: 
In LDG methods, we introduce an auxiliary variable p to represent the derivative of the primary variable u, and solve them on the same mesh. In this talk, we will introduce a new LDG method, and solve u and p on different meshes. The stability and error estimates will be investigated. The new algorithm is more flexible and flux-free for pure diffusion equations without introducing additional computational cost compared with the original LDG methods, since it is not necessary to solve each equation twice. Moreover, it is possible to construct third-order maximum-principle-preserving schemes based on the new algorithm. However, one cannot anticipate optimal accuracy in some special cases. In this talk, we will find out the reason for accuracy degeneration which further leads to several alternatives to obtain optimal convergence rates. Finally, several numerical experiments will be given to demonstrate the stability and optimal accuracy of the new algorithm.