Electronic Theses and Dissertations

Date of Award


Document Type


Degree Name

M.S. in Engineering Science

First Advisor

Dr. Taiho Yeom

Second Advisor

Dr. Taiho Yeom

Third Advisor

Dr. Tyrus McCarty

Relational Format



Experimental and numerical studies were carried out to investigate the convection heat transfer enhancement of air channel flow using a piezoelectric fan, operated at 90.3 Hz. Its peak-to-peak displacement was increased up to 11.8 mm. The average velocity of channel flow was ranged up to 3 m/s, covering both laminar and turbulent flow regimes. The effects of fan location on the heat transfer performance were evaluated by changing the relative position of the fan tip to the heated surface. A maximum heat transfer enhancement of 102 % was obtained at the channel flow rate of 15 LPM. The fan was placed at the front-end location of the heated surface and operated with a displacement of 11.8 mm. For a fixed channel flow condition, the piezoelectric fan was found to improve the heat transfer performance only when operated with displacements larger than the critical value. The overall heat transfer performance of the heated surface in the channel was found to be dependent on the channel volume flow rate and the amplitude and frequency of the piezoelectric fan. The numerical study was performed using ANSYS Fluent to investigate complex flow fields created by the piezoelectric fan and their impact on the thermal responses of the heated surface in the channel. The Q-criterion analysis was used to identify vortical structures generated from the piezoelectric fan and understand their transport characteristics. It was found that the formation, propagation, and impinging dynamics of vortical structures were the significant factors that affected the convective heat transfer rate of the heated surface in the channel.



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