Nariman Ashrafi*
The Journal of Mechanical Science and Technology, vol. 25, no. 9, pp.2247-2257, 2011

Abstract : The shear thinning Taylor-Couette flow is studied in the narrow gap limit. The fluid is assumed to follow the Carreau-Bird model and mixed boundary conditions are imposed. The low-order dynamical system, resulted from Galerkin projection of the conservation of mass and momentum equations, includes additional nonlinear terms in the velocity components originated from the shear-dependent viscosity. It is observed that the base flow loses its radial flow stability to the vortex structure at a lower critical Taylor number as the shear thinning effects increases. The emergence of the vortices corresponds to the onset of a supercritical bifurcation which is also seen in the flow of a linear fluid. Complete flow field together with stress and viscosity maps are presented for different scenarios in the flow regime.

Keyword : Shear thinning; Nonlinear stability analysis; Galerkin projection; Taylor-Couette flow