Optimal design of miniature piezoelectric fans for cooling light emitting diodes

Piezoelectric fans have emerged as a viable cooling technology for the thermal management of electronic devices with their low power consumption, minimal noise emission, and small and configurable dimensions. In this work, these fans are investigated for application in the cooling of electronics components and light emitting diodes (LEDs). Different experimental configurations are considered, and the effect of varying the fan amplitude, the distance between the fan and the heat source, the fan length, its frequency offset from resonance, and the fan offset from the center of the heat source are studied to assess the cooling potential of piezoelectric fans. A design-of-experiments (DOE) analysis revealed the fan frequency offset from resonance and the fan amplitude as the critical parameters. Transfer functions are obtained from the DOE analysis for the implementation of these fans in electronics cooling. For the best case, an enhancement in convective heat transfer coefficient exceeding 375% relative to natural convection was observed, resulting in a temperature drop at the heat source of more than 36.4/spl deg/C.