Heat transfer prediction of rotating rectangular channels using reynolds stress model

Computations were performed to study three-dimensional turbulent flow and heat transfer in a rotating smooth rectangular channel with channel aspect ratio of 4:1. Two channel orientations (β = 90 and 135 deg from the rotation direction) were investigated, focusing on the high-rotation and high-density-ratio effects on the heat-transfer characteristics of the 135-deg orientation. The rotation number and inlet coolant-to-wall density ratios, Δp/p, were varied from 0.0 to 0.28 and from 0.122 to 0.40, respectively; the Reynolds number was fixed at 10⁴. The effect of rotation and coolant-to-wall density ratio on the fluid flow and heat transfer characteristics is reported. The study shows considerable spanwise heat transfer differences across the leading and trailing surfaces. Also, it indicates complete flow reversal in the leading part of the channel, altering heat-transfer characteristics. The numerical results are compared with the experimental data for both stationary and rotating rectangular channels.