A 3rd order upwind finite volume method for generalised Newtonian fluid flows

摘要

The non-Newtonian effects in the flow of non-Newtonian fluids that can be modelled with generalised Newtonian constitutive equations are investigated using a numerical scheme based on the finite volume formulation. Collocated arrangement of variables is used and the pressure-correction method in conjunction with the SIMPLE scheme is applied. In order to avoid the diffusive effects of low order schemes, the approximation of the convection terms is carried out using the QUICK differencing scheme, which is of third order of accuracy. For modelling viscous non-Newtonian behaviour, the Power-Law, Quemada and the modified Bingham and Casson models are employed. Validation of the code is carried out upon comparison with numerical data available in the literature. Exploiting the lid-driven cavity flow a twofold investigation is carried out regarding the non-Newtonian effects first by using different models and secondly by using the shear-thinning and shear-thickening attributes of the fluid.