Vortex shedding from a circular cylinder in shear-thinning Carreau fluids

Results from numerical simulations of two-dimensional, shear-thinning Carreau fluid flow over an unconfined circular cylinder are presented in this paper. Parametric sweeps are performed over the various Carreau model parameters, and trends of the time-averaged force coefficients and vortex characteristics are reported. In general, increased shear-thinning results in lower viscous forces on the body but greater pressure forces, resulting in a complex non-monotonic drag response. Lift forces generally increased with shear-thinning due to the dominant pressure contribution. The decrease in fluid viscosity also led to shorter vortex formation lengths and the consequent rise in the Strouhal frequency of vortex shedding. It is expected that these results will be useful for verification of computational models of unsteady non-Newtonian flows.