RT Journal Article ID 3c5e483c37d650f2 A1 Hsu, Heng-Pin A1 Cheng, Chao A1 Li, Hung-Yi A1 Sheu, Tsung-Sheng A1 Ay, Herchang T1 THERMAL AND FLUID CHARACTERISTICS OF SINGLE FIN HEAT SINK WITH A PIEZOELECTRIC COOLING FAN JF Journal of Flow Visualization and Image Processing JO JFV YR 2019 FD 2019-01-03 VO 26 IS 1 SP 57 OP 78 K1 piezoelectric fan K1 flow field K1 particle image velocimetry K1 thermal cooling AB This paper presents a comparative investigation of numerical flow simulations and the experimental data of a piezoelectric fan by particle image velocimetry. It investigates the fluid mechanics of a piezoelectric fan operating in its vibration frequency mode. The experimental results show that the optimal driving frequency for the piezoelectric fan is 60 Hz. At this frequency, the thin blade of the piezoelectric fan reaches its maximum vibration amplitude. The flow field visualization obtained in the experiments shows that the amplitude of the fan blade directly affects flow velocity. The vortex structures exhibit irregular motion once they separate from the blade tip. The phase measured PIV results are presented in terms of vorticity and show the formation of a horse shoe vortex. A maximum flow velocity of 1.7 m/s is obtained. It was also observed that the vibrating blade induces a pair of vortices, one clockwise and one counterclockwise. The blade vibration induces a pair of vortices around the blade tip. The blade inhale and propulsion air flow induces a jet-like motion at the tip during a cycle. Its fast blade motion achieves thermal cooling. PB Begell House LK https://www.dl.begellhouse.com/journals/52b74bd3689ab10b,6368d04933435128,3c5e483c37d650f2.html