Modeling and simulation of wetting and spreading

Abstract

We present a mathematical model for the slow three-dimensional motion of a liquid coating on a substrate with wetting and de-wetting edges. The equilibrium contact angle is considered to be a material property of the liquid-substrate system. Substrate chemical heterogeneity, or physical roughness, may also be an important determinant of edge motion. Conversely, dynamic contact angle information is not required by the model; it is predicted as part of the solution. Calculated results are compared with experimental observation with good agreement. Many industrial applications involve liquid coating and wetting considerations are usually quite important. References

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