Numerical Study on Flow of Non-Newtonian Power Law Fluids Acrossan Arched Roughened Circular Cylinder

Numerical analysis to investigate the flow characteristics of non-Newtonian power-law fluids across a roughened circular cylinder has been done using ANSYS Fluent 18.0. The Reynolds number ( Re)and power-law index (n) of the flow vary in the range of 1 <= Re <= 40 and 0.25 <= n <= 1.5 respectively.The flow characteristics have been analyzed in terms of pressure (C-dp), friction (C-df) and total drag coefficients (C-d) withRe and nas variable parameters. The detailed flow visualization has been done with the help of streamlines and vorticity contours. All else being similar C-dp and C-df decrease with Re. The C-d for dilatant fluid is less than the Newtonian fluid for Reynolds number up to 10, whereas,for Re> 10, the C-d for Newtonian fluid is less than the dilatant fluid, under otherwise identical situations. C-d on the roughened circular cylinder is significantly higher than the simple circular cylinder.