In this study, the effect of stationary and oscillating blades on the forced convection heat transfer in a channel are studied numerically. Simulations are performed in a fully-developed, laminar, unsteady, and incompressible flow with Reynolds number and Prandtl number equal to 100 and 1, respectively. The effects of blade geometry, oscillating speed and oscillation angle on heat transfer and pressure drop are studied. The results are presented in terms of time averaged Nusselt number, temperature and vorticity distribution and the pressure drop. The results indicate that the oscillation angle and oscillating speed of the blade and the number of the blades, affect the thermal performance of the channel. For most cases, it was observed that the effect of the oscillation angle is more than that for the oscillating speed on heat transfer enhancement. However, increasing the number of blades does not necessarily help to enhance the heat transfer, but it can slightly decrease the pressure drop.