Variational Approach to Homogenization of Doubly-Nonlinear Flow in a Periodic Structure

This work deals with the homogenization of an initial- and boundary-value problem for the doubly-nonlinear system $$D_t w -\nabla\cdot \vec z = \nabla\cdot \vec h(x,t,x/\varepsilon), \qquad w\in \alpha(u,x/\varepsilon), \qquad \vec z\in \vec\gamma(\nabla u,x/\varepsilon).$$ Here $\varepsilon$ is a positive parameter, and the prescribed mappings $\alpha$ and $\vec\gamma$ are maximal monotone with respect to the first variable and periodic with respect to the second one. The two inclusions are here formulated as null-minimization principles, via the theory of Fitzpatrick [MR 1009594]. As $\varepsilon\to 0$, a two-scale formulation is derived via Nguetseng's notion of two-scale convergence, and a (single-scale) homogenized problem is then retrieved.