zbMATH — the first resource for mathematics

Applications of variational inequalities to a moving boundary problem for Hele Shaw flows. (English) Zbl 0605.76043
We consider a class of two-dimensional moving boundary problems, originating from a Hele Shaw flow problem. Concepts of classical and weak solutions are introduced. We show that a classical solution also is a weak solution and, by using variational inequalities, that given arbitrary initial \((t=0)\) data there exists a unique weak solution defined on the time interval \(0\leq t<\infty\). We also prove some monotonicity properties of weak solutions and that, under reasonable hypotheses, the moving boundaries consist of analytic curves for \(t>0\).

76D10 Boundary-layer theory, separation and reattachment, higher-order effects
46E35 Sobolev spaces and other spaces of “smooth” functions, embedding theorems, trace theorems
35Q30 Navier-Stokes equations
Full Text: DOI