Numerical Simulation of Fiber Suspension Flow between Parallel Plates.

Abstract

Two-dimensional fiber suspension flow between parallel plates was simulated using the Dinh-Armstrong constitutive equation for semi-concentrated fiber suspensions. Sixth-order and fourth-order closure approximations were also evaluated. The velocity profile for the fiber suspension flow is flat compared with Newtonian flow, because the preferred angle for fibers is large in the channel center region, resulting in an increase in the local viscosity. The order parameter decreases and the preferred angle becomes large with increasing fiber concentration. The velocity field is accurately predicted by the equations with quadratic closure approximations used in this study, whereas the approximations do not provide satisfactory results for the orientation field. With respect to the order parameter, sixth-order closure approximation gives slightly less accurate predictions than fourth-order approximation.