Long-time behavior of a Hele-Shaw type problem in random media

Abstract

We study the long-time behavior of an exterior Hele–Shaw problem in random media with a free boundary velocity that depends on the position in dimensions $n\ge 2$. A natural rescaling of solutions that is compatible with the evolution of the free boundary leads to the homogenization of the free boundary velocity. By studying a limit obstacle problem for a Hele–Shaw problem with a point source, we are able to show the uniform convergence of the rescaled solution to a self-similar limit profile and we deduce that the rescaled free boundary uniformly approaches a sphere.