学术活动

A general approach to stability in free-interface problems

作者:   来源:  时间:2015-06-24

主题:A general approach to stability in free-interface problems

主讲人:Prof. Claude-Michel BRAUNER Xiamen University, China

时间:2015年6月24日 15:00—2015年6月24日 16:00

地点:北二区教学楼 133 教室

面向对象:全体师生

简介:

In two-dimensional free-interface problems in combustion theory, we have defined two different approaches to study the stability of the front flame, which actually complement each others: (i) the first one is the elimination of the free interface,. Then, the problem is fully nonlinear with boundary conditions of Hadamard type. This method is quite general and applies to a large class of Free Boundary Problems. (ii) the second approach is the derivation of a single scalar equation for the front which may capture most of the dynamics and, as a consequence, yields a reduction of the effective dimensionality of the system. A paradigm is the Kuramoto-Sivashinsky equation which models cellular instabilities and turbulence phenomena. In a previous talk we presented the second method. We are now going to focus our attention on the first approach which is quite efficient to prove stability or instability of moving fronts. In particular, we will discuss a combustion problem with two free interfaces (work in progress with Wen ZHANG).