Abstract: The study of wetting phenomenon is of critical importance for many applications and has attracted much interest, stimulated by the development of surface engineering and the studies on the superhydrophobicity property in a variety of nature and artificial objects. There are many interesting problems in this field, such as free interface, moving contact line in two-phase fluids, multi-scale phenomena induced by rough boundaries. In this talk, I will illustrate our recent studies in this field. Starting from a simplified model, which includes only interface effects, we analyze the well-posedness of a Cahn-Hilliard equation with relaxed boundary condition, the sharp-interface limit, homogenization for rough boundaries and chemically patterned surfaces. By these analyses, we investigate some interesting physical properties of wetting, like Wenzel's and Cassie's equation for macroscopic contact angles, contact angle hysteresis, and dynamics of the contact angle. Then we illustrate some numerical studies on two-phase flow with moving contact line and partial differential equations in domain with rough boundaries. These numerical methods are expected to be used to simulate the wetting problem in the future. Finally, we introduce an application of wetting in two-phase porous media flow. A non-Darcy behavior is discovered through a carefully analysis for a channel flow with patterned surface. The results are verified by numerical simulations.

   

Date&Time: June 24, 2013 (Monday), 15:00 - 16:00
Location: 606 Conference Room