Laminar flow past three closely spaced monodisperse spheres or nonevaporating drops

Abstract

A basic understanding of the highly nonlinear interaction effects of multiple, closely spaced spheres or droplets on the fluid flow patterns and fluid mechanics parameters is of importance for the improved design of a variety of fluid-particl e systems. Streamlines, vorticity contours, flow separation angles, and individual drag/interaction coefficients are presented for steady laminar axisymmetric flow past a linear array of three spheres or droplets. A finite element method has been used to solve the complete Navier-Stokes equations for the system parameter ranges of 1 < Red < 200 (particle Reynolds numbers) and 2 < dy < 6 (dimensionless particle spacings). The verified computer simulation results indicate that the separation angles and effective drag coefficients of interacting spheres deviate significantly from solitary spheres at all Reynolds numbers. The differences between solid spheres and nonevaporating water drops in air with stress-induced internal circulation are only marginal.