CFD Analysis of Two-Dimensional Non-Newtonian Power-Law Flow across a Circular Cylinder Confined in a Channel

Flow of non-Newtonian power-law fluids across a long circular bluff body confined symmetrically between infinitely long two parallel plane walls is investigated numerically by solving the continuity and momentum equations using the finite volume method-based solver Fluent. The numerical calculations are performed in the full computational domain for the following ranges: Reynolds number = 50-150 and power-law index = 0.4-1.8 (covering shear-thinning, Newtonian, and shear-thickening behaviors) for the blockage ratio of 0.25. Global characteristics such as drag and lift coefficients, and Strouhal number and derived variables such as stream function are calculated for the above range of conditions. It is observed that the shear-thinning behavior yields a lower value of the time-averaged drag coefficient than the corresponding Newtonian value; however, an opposite trend is observed in the shear-thickening behavior. The Strouhal number increases with increasing Reynolds number for the fixed value of the power-law index.