科学研究
报告题目:

Long time behavior of 2d water waves with point vortices

报告人:

苏庆堂 (University of Southern California)

报告时间:

报告地点:

2021欧洲杯买球平台官网东北楼四楼报告厅(404)

报告摘要:

we study the motion of the two dimensional inviscid incompressible, infinite depth water waves with point vortices in the fluid. We show that Taylor sign condition $-\frac{\partial P}{\partial \boldmath{n}}\geq 0$ can fail if the point vortices are sufficient close to the free boundary, so the water waves could be subject to the Taylor instability. Assuming the Taylor sign condition, we prove that the water wave system is locally wellposed in Sobolev spaces. Moreover, we show that if the water waves is symmetric with a certain symmetric vortex pair traveling downward initially, then the free interface remains smooth for a long time, and for initial data of size $\epsilon\ll 1$, the lifespan is at least $O(\epsilon^{-2})$. If the initial data is localized, then the solution exists globally.