The Effect of Rib's Shape Change in Improvement of Thermal Performance in Rotational Ribbed Cooling Channels

In the present work, numerical simulation with Reynolds stress model has been developed to study the thermal performance of square channel with various-shaped 90˚ ribs fixed on walls in staggered pattern. The simulations were performed for three type of rib shapes, i.e., square, trapezoidal, and trapezoidal with decreasing height in the flow direction. The Reynolds number is 25,000 and rotation number is 0.12. The simulation indicates the distribution of thermal performance in one period of ribs. The results show that features of the inter-rib distribution of heat transfer coefficient are strongly affected by the rib shape and trapezoidal ribs provide higher heat transfer enhancement and pressure drop than the other ones. Trapezoidal rib efficiency is 40.62% higher than smooth channel and 2.6% higher than square rib.