Homogenization of a fluid problem with a free boundary

The stationary Stokes equations with a free boundary an: studied in a perfo rated domain. The perforation consists of a periodic array of cylinders of size and distance O(epsilon). The free boundary is given as the graph of a function on a two-dimensional perforated domain. We derive equations for th e two-scale limit of solutions, The limiting equation is a free boundary sy stem. It involves a nonlinear elliptic operator corresponding to the nonlin ear mean-curvature expression in the original equations, Depending on the e quation for the contact angle, the pressure is in general unbounded. (C) 20 00 John Wiley & Sons, Inc.