Global regularity of 2D density patches for inhomogeneous Navier-Stokes
arXiv:1612.08665
Abstract
This paper is about Lions' open problem on density patches \cite{LIONS}: whether inhomogeneous incompressible Navier-Stokes equations preserve the initial regularity of the free boundary given by density patches. Using classical Sobolev spaces for the velocity, we first establish the propagation of regularity with in the case of positive density. Furthermore, we go beyond to show the persistence of a geometrical quantity such as the curvature. In addition, we obtain a proof for regularity.
Some typos corrected, added references and comments about free boundary conditions, introduction expanded, 22 pages