Piezoelectric fans are an effective device for heat transfer enhancement in low convective regions due to their low power consumption, low noise, and operational simplicity. This study performs a numerical and experimental investigation into the effects of a piezoelectric fan on the velocity and temperature fields near a cylindrical heat source with a constant heat flux on the sidewalls and upper flat surface. In performing the investigation, the blade is placed at various locations along the cylindrical axis and is arranged such that it vibrates in either the vertical direction or the horizontal direction. The results show that the airstream induced by the vibrating fan covers a broader area of the heated surface when the blade vibrates in the vertical direction, and therefore yields a better heat transfer performance than that achieved when the fan vibrates in the horizontal direction. In addition, it is found that the maximum heat transfer augmentation ratio is obtained at dimensionless fan positions ranging from 0.6 to 0.75, and has values of 1.94, 1.53, and 1.44 given dimensionless fan tip clearances of 0.5, 1.0, and 1.5, respectively. Finally, it is shown that while the numerical results underestimate the effect of the vibrating piezoelectric fan in enhancing the heat transfer performance by around 1-14%, a good qualitative agreement is observed between the numerical and experimental results.