Study of thermal and flow characteristics of a heated cylinder under dual piezoelectric fans actuation

Piezoelectric fan has been considering as an enhanced heat transfer device since the size of modern electric products continues to decrease and the heat dissipation per unit volume is growing rapidly. The present study analyzed the flow mechanism and heat transfer performance of dual fans installed on the both opposite sides of a heated cylinder. Three different vibration phases; the in-phase, counter-phase and perpendicular-phase were proposed to evaluate the suitable dual piezoelectric fans arrangement for getting the effective heat transfer enhancement. The numerical results showed the detailed streamlines and velocity vectors around the piezoelectric fans and heated cylinder. In addition, the average surface temperatures with the position of piezoelectric fan for three phases were sketched to indicate the heat transfer performance. A maximum heat transfer augmentation ratio of 3.20 is achieved for the dual fans vibrated in-phase at the installed position of y/H = 0.625.