题目：Spectral constraint and initial-boundary layer associated with the nonlinear Darcy-Brinkman system

　　报告人：Prof. Xiaoming Wang（Florida State University）

　　摘要：Many physical models are simplified models that are derived by formally setting certain non-dimensional parameters to zero. The original models can be viewed as perturbations of the limit models. These perturbations are singular in many applications in the sense that there exist singular structures in the limit. The rigorous verification of such singular limits are of physical importance in terms of model validation and in terms physical phenomena that may require the understanding of the singular structures. One well-known example is the inviscid limit of the Navier-Stokes system in the presence of physical walls. The rigorous validation of the Euler system as the inviscid limit of the Navier-Stokes system is still a prominent open problem. In this talk, I will identify the important role played by spectral constraint associated with appropriately constructed approximate solutions.  We illustrate the application of the spectral constraint approach to several examples, including  the vanishing Darcy number limit of the nonlinear Darcy-Brinkman system. The limit is a singular one that involves the interaction of an initial layer and boundary layers. 

　　时间：8月12日（周三）下午16:30-17:30

　　地点：澳门沙金在线平台北一区文科楼 707 教室

　　欢迎全体师生积极参加！