Numerical simulation of non-newtonian flows through ducts with axisymmetric expansions using power-law model

Abstract

This work presents a method to simulate incompressible non-Newtonian flows through a duct with axisymmetric sudden expansion, with emphasis to the expansion ratios. The governing equations are solved using the finite-differences explicit Runge-Kutta time-stepping scheme in nondimensional form in which continuity and momentum are solved simultaneously along the grid points. The power-law model is applied to predict pseudoplastic and dilatant behavior. Numerical results for some expansions ratios are presented for Re=20 and show a good agreement with the theory for these flows. Palavras-Chave: Numerical simulation, axisymmetric abrupt expansion, non-Newtonian flow.