Convective heat transfer enhancement in a parallel plate channel by means of rotating or oscillating blade in the angular direction

In this paper, the effects of a rotating and oscillating blade, as an active technique, inside a parallel plate channel on the forced convection heat transfer for steady and unsteady laminar flow was studied numerically. As such, influence of the oscillation angle, revolutions per minute (rpm), and the Prandtl number on heat transfer enhancement were investigated for Reynolds numbers of 50 and 100. The results were presented in terms of the local and average Nusselt numbers, temperature, and vorticity contours along the channel and compared with available results for the straight channel, stationary blade, stationary, oscillating and rotating circular cylinder. It was found that the heat transfer enhancement was more significant for the oscillating blade and the stationary blade cases at Re = 50 and Re = 100, respectively.