Flow Resistance and Mass Transfer in Slow Non-Newtonian Flow Through Multiparticle Systems

Abstract

Finite difference solutions for a power-law fluid flow through an assemblage of solid particles at low Reynolds numbers are obtained using both the free-surface cell model and the zero-vorticity cell model. It is shown that, unlike in the case of power-law fluid flow past a single solid sphere, the flow drag decreases with decrease of flow behavior index, and that the degree of this reduction is more significant at low voidage. The results from this study are found to be in good agreement with the approximate solutions at slight pseudoplastic anomaly and the available experimental data. The results are presented in closed form and compare favorably with the variational bounds and the modified Blake-Kozeny equations. Numerical results show that a decrease in the flow behavior index leads to a slight increase in the mass transfer rate for an assemblage of solid spheres, but this increase is found to be small compared with that for a single solid sphere.