Special Session 49: Growth Models and Interface Dynamics

Thin liquid films or foam films are the basic constituents of emulsions, or foams and are important for a wealth of applications ranging from process engineering to everyday articles of use as shampoos or soft drinks. The interface processes are highly interesting and of fundamental interest for physics, physical chemistry, engineering and eventually mathematics. Thin film theory is worked out and understood to a reasonable degree for films on a horizontal or inclined surface. Free-standing,vertical films are di↵erent in that they have two free surfaces and consequently the physics of the surfactants play a dominant role. Whereas the equilibrium properties of such free-standing foam films are investigated experimentally and theoretically, transient processes and nonequilibrium dynamics in general are still an area to explore. We present a summary of experimental results for foam films driven by a thermal gradient or electromagnetic forces. Further, we give the basic equations using lubrication theory and explain the relevant dynamics in terms of partial di↵rerential equations. A numerical approach using lattice Boltzmann method is presented with first quantitative results. In particular, we present experiments and discuss the propagation of a stable front of so-called balck film (on the nanometer scale) into the unstable thicker material.