Direct numerical simulation of spanwise rotating channel flow and heat transfer

The effects of spanwise rotation on the turbulent channel flow and heat transfer were examined with direct numerical simulation (DNS). The unsteady N-S equations were discretized by finite difference method. The Reynolds number based on half channel width and friction velocity and the Prandtl number were set to be 150 and 0.71, respectively. Grid number was 64 × 128 × 64. Our computational results indicate that the turbulent intensity increased and heat transfer is enhanced at the pressure side with increasing rotation number, while heat transfer is suppressed at the suction side. Moreover, the rotation terms in the Reynolds stress transport equations play more important role in the redistribution of energy among different direction than the pressure-redistribution terms, and they change drastically the budget of Reynolds stress equations. In addition, in the pressure side, the effect of Coriolis force makes the low-speed streaks slenderer and the space between streaks smaller, and in the suction side, streaks almost disappear and the flow has the tendency to become laminar.