THERMAL MANAGEMENT
Piezoelectric fans
Piezoelectric fans offer a low-power solution for airflow generation and convective heat transfer enhancement in electronics with limited access to energy sources. These fans typically consist of flexible plates that are vibrated near their resonance frequency using piezoelectric actuators.
Our research focuses on understanding the fascinating physics involved in airflow generation using these fans. This encompasses all aspects of their complicated power consumption mechanisms, vortex dynamics, and three-dimensional jet topology. We aim to correlate these physics to the cooling performance of the fans and thereby facilitate their design optimization based on application.
Three-dimensional vortex structures in the wake of piezoelectric fans.
Vortex propagation sequence on the midspan plane of a piezoelectric fan.
Novel wicks for phase change heat transfer devices
We develop advanced hierarchical wicks for two-phase heat transfer devices, especially vapor chambers and heat pipes. In a DARPA-funded project, we demonstrated vapor chambers called TGPs (Thermal Ground Planes) for high-flux AND high-power electronic and optoelectronic devices.
One version of our wick is fabricated using microfabrication techniques and its surface is nanostructured to achieve extreme wetting characteristics for water, a preferred working fluid due to its very high latent heat, heat capacity, and thermal conductivity.
