Effect of an Asymmetrically Confined Rotating Cylinder on Heat Transfer

For an asymmetrically confined rotating cylinder placed at the axis of a channel, surrounded with the flow of power-law fluid has been numerically investigated here. The dimensionless parameters used to solve the governing equations numerically are Reynolds number, Prandtl number and power law index which have the values as 0.1 ≤ Re ≤ 40, 0.7 ≤ Pr ≤ 100, 0.3 ≤ n ≤ 1 respectively, the value of asymmetrical ratio and blockage ratio varies as 0.1 ≤  \(\Upsilon\)  ≤ 1 and 0.2 ≤ β ≤ 0.6 respectively. For keeping the two Reynolds number equal, at the inlet section average velocity should be same as that of angular velocity. Streamlines are used for the visualization of flow and isotherms represent the temperature profile at different positions of the cylinder. In most cases, the flow is made more stable by having a moderate degree of cylinder confinement. However, arrangement of the high Reynolds number, the high shear-thinning behaviour of the fluid and the degree of symmetry become more promising than the cylinder confinement to determine the flow behaviour, and resulting to shift the flow field from being steady to being time-dependent. Although, the extent of transition takes longer to take place as the cylinder gets closer to one of the channel walls.