Effect of cylinder geometry on the heat transfer enhancement of power-law fluid flow inside a channel

Abstract

The heat transfer enhancement and pressure drop of non-Newtonian power-law fluid flow due to the presence of a bluff body inside a channel are numerically investigated. Different cross-section geometries such as circular, elliptical, trapezoidal, and inclined square cylinders with the angles of 0°, 15°, 30°, and 45° are studied and compared with straight channel. The results are presented as streamlines, local and average Nusselt number, friction factor and thermo-hydraulic performance for the Reynolds number of 10, 20, and 30, Prandtl number of 100, and power-law index of 0.4, 0.6, 0.8, and 1. The blockage ratio is considered as 0.25 for all the cases. The results show that the thermo-hydraulic performance increases by decreasing the power-law index and the square cylinder with inclined angle of 45° has maximum thermo-hydraulic performance. The effect of the cylinder geometry on the heat transfer enhancement was more than that of the power-law index.