Numerical Analyses on the Adhesive Contact between a Sphere and a Rough Surface

Compared to the macro-contact, both adhesion and elastic force are important in the micro/nano-contact. Thus, micro/nano-contact is also called adhesive contact. In micro/nano-technology and MEMS, the adhesive contact between a sphere and a rough surface is an important issue. This research is focused on the phenomena and the computation algorithm for the micro/nano adhesive contact between a sphere and a rough surface. Lennard-Jones potential is used to govern the traction. Convolution of FFT is used to compute the displacement of rough surfaces. Inexact Newton Bi-CGSTAB method is used to solve the system of nonlinear equations. Preconditioners are used to speed up the computation. The relation of contact area/load is used to check the accuracy of the computation. Stagnation may happen in iteration. In order to find the best algorithm, different preconditioners, line-search, relaxation factor, genetic algorithm and particle swarm optimization are tested. The research will find the best algorithm and the effect of rough surface on the adhesive contact between a sphere and a half-space. The research result can be applied in the basic research in adhesive contact, and can also be applied in real MEMS system and nano-technology.

Project ID:PB10708-2423
External Project ID:MOST107-2221-E182-047