Transverse mobility prediction of non-Newtonian fluids across fibrous porous media

Abstract

This work is an extension of our previous work [Wang JF and Hwang WR. Permeability prediction of fibrous porous media in a bi-periodic domain. J Compos Mater 2007; 42: 909-929], in which a finite-element fictitious-domain mortar-element technique was developed to investigate the permeability of fibrous porous media in the bi-periodic domain, to non-Newtonian shear-thinning fluid. Considering the amount of shear-thinning, the pressure drop, the fiber microstructure, and the porosity as parameters, we investigate (i) the (normalized) mobility and its dependence on both the amount of shear-thinning and the given pressure drop; (ii) mechanisms leading to the main flow path in a highly shear-thinning fluid in randomly distributed fiber problems, and (iii) inter-tow and intra-tow non-Newtonian flow characteristics in a fiber bundle problem. The dependence of the mobility on shear-thinning has been found to appear completely opposite according to given pressure drop values.