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.