学术报告：10月21号14:30-15:30，台湾高雄大学--吴宗芳

报告人

鲁汪涛

单位

浙江大学

报告题目

Wave scattering problems in two-layered media: condition at infinity and   numerical methods

报告时间

2019.10.21

14:30-15:30

地点

九龙湖校区数学学院教工活动室

邀请人

王海兵

报告摘要

In this talk, I will   present some recent results for wave scattering in a two-layered medium by   one of the following two reduced rough surfaces: a local perturbation of a   straight line, and a step-function surface with a finite vertical segment, a   global perturbation of a straight line. To ensure the wellposedness, it is   known that the angular spectral representation (ASR) condition can be imposed   at infinity. However, ASR condition is not easy to use for truncating the   unbounded domain. To overcome this issue, we desire sharper radiation   conditions that can extract purely outgoing waves from the total wavefield.   For the locally perturbed surface, it has been proven that the perturbed   wavefield due to the local perturbation is purely outgoing at infinity. Based   on this sharper radiation condition, I will present a PML-based boundary   integral equation (BIE) method to solve the scattering problem.  For the   globally perturbed surface, I will introduce a new radiation condition at   infinity which, as was desired, extracts outgoing waves at infinity, and will   present a PML-based numerical mode matching method to solve the problem.   Numerical results will be presented to demonstrate the performance of our   methods.

报告人

简介

鲁汪涛，浙江大学特聘研究员。2012年获得中国科学技术大学计算数学博士学位和香港城市大学哲学博士学位，2013—2017年先后在香港城市大学和密歇根州立大学做博士后。2017年至今，任浙江大学数学科学学院任特聘研究员。主要研究方向为正反散射问题、光子晶体结构的建模和计算等。