Display Abstract

Title The two-phase porous medium equation: asymptotic behavior of weak solutions

Name Bogdan Matioc
Country Germany
Email matioc@ifam.uni-hannover.de
Co-Author(s) Philippe Laurencot
Submit Time 2014-02-21 10:19:48
Session
Special Session 39: Interfaces in fluid mechanics
Contents
We discuss the asymptotic behavior of globally defined non-negative weak solutions of the two-phase porous medium equation \begin{equation*} \left\{ \begin{array}{rcl} \partial_t f & = & \partial_x\left(f\partial_x\left( (1+R)f+Rg\right)\right),\\ \partial_t g & = & R_\mu\partial_x\left(g\partial_x\left( f+g\right)\right), \end{array} \right. \qquad (t,x)\in (0,\infty)\times \mathbb{R}, \end{equation*} whereby $R$ and $R_\mu$ are positive parameters. This strongly coupled degenerate parabolic system was obtained as the thin film approximation of the Muskat problem. The existence of globally defined non-negative weak solutions is established by interpreting the system of evolution equations as a gradient flow for the $L_2-$Wasserstein distance. This system possesses a rich landscape of self-similar symmetric and non-symmetric Barenblatt type profiles. We show that any non-negative global solution converges in the large towards a self-similar solution of the problem.