Keywords: plane symmetric expansion, symmetry-breaking phenomena, inelastic shear-thinning fluid, power law model, finite volume methodPublished in DKUM: 01.06.2012; Views: 1718; Downloads: 81 Link to full text
Abstract: The goal of a present study is to investigate the effects of generalized Newtonian fluids on the threshold of the transition from flow symmetry to its asymmetry for the flow through a locally constricted channel. We consider purely viscous shear-thinning fluid and compare it with the Newtonian fluid. Fluid flow is studied numerically by solving the two dimensional momentum equations along with the continuity equation and the Carreau-Yasuda rheological model. We report systematic results in a range of generalized Reynolds number 250▫$leq$▫Re▫$leq$▫150 with a focus on its critical value. Results indicate that the shear-thinning viscous behaviour decreases the onset of bifurcation phenomena and the critical value of Reynolds number. Last but not least, a systematic grid refinement analysis and numerical accuracy study is performed and present numerical results may be treated as the benchmark.Keywords: bifurcation, inelastic shear-thinning fluid, Carreau-Yasuda model, numerical modellingPublished in DKUM: 31.05.2012; Views: 1614; Downloads: 129 Link to full text