W. G. Pritchard Lab Seminar: 4-5 PM, 116 McAllister Building

	          **Tuesday April 30, 2002**
	
Dynamics and Stability of Van der Waals Driven Thin Film Rupture

Andrew J. Bernoff

Department of Mathematics
Harvey Mudd College

Abstract:

Fluid films of micron and sub-micron thickness arise as optical coatings,
photographic emulsions and insulating layers in electronic circuits. At
this lengthscale van der Waals and capillary forces dominate; a
lubrication model for the film's evolution was derived by Williams &
Davis (1982). More recently, Zhang & Lister (1999) showed that this model
has an infinite set of similarity solutions corresponding to finite-time
film rupture. In this talk, I examine the dynamics and stability of thin
film rupture in planar and axisymmetric geometries.  I also will discuss
strategies for regularizing the model by incorporating repulsive van der
Waals forces so that the evolution can be continued beyond rupture to the
formation of droplets. Finally, I will discuss some of the limitations of
the lubrication approximation, and a method for studying existence and
stability of fully nonlinear equilibrium drop solutions.