Abstract
The effect of surface roughness on developed laminar flow in microtubes is investigated. The tube boundary is defined by r = R[1 + epsilon sin(lambda theta)], with R representing the reference radius and epsilon and lambda the roughness parameters. The momentum equation is solved using Fourier-Galerkin-Tau method with slip at the boundary. A novel semi-analytical method is developed to predict friction factor and pressure drop in corrugated rough microtubes for continuum flow and slip flow that are not restricted to small values of epsilon lambda. The analytical solution collapses onto the perturbation solution of Duan and Muzychka (J. Fluids Eng., 130: 031102, 2008) for small enough values of epsilon lambda.