EFFECTS OF SURFACE ROUGHNESS ON FLOWS THROUGH NANO/MICRO CHANNEL BASED BIOMEDICAL DEVICES - A STUDY BY LATTICE BOLTZMANN METHOD

摘要

The objective of this research is to study the effects of surface roughness on flows through nano/micro channels with a focus on designing better biomedical devices. A two dimensional computational model for fluid flow based on Lattice Boltzmann (LB) method has been applied first to a 10 μm width channel with flat boundary conditions and the flow profiles have been found to have an excellent comparison with analytical results. Rough boundary conditions using rectangular tooth-shaped corrugations giving about 0.25 μm average roughness have then been applied to the same 10 μm channel flow. We have observed significant differences in the velocity profiles between the flows with rough and flat boundary conditions. Boundary slips have also been observed in case of flows with rough boundary conditions. Surface roughness effects have increased or the differences between the flows with rough and flat boundary conditions have increased with decreased channel widths.