Experimental Study of Flexible Electrohydrodynamic Conduction Pumping for Electronics Cooling

Abstract

As modern-day electronics develop, electronic devices become smaller, more powerful, and are expected to operate in more diverse configurations. However, the thermal control systems that help these devices maintain stable operation must advance as well to meet the demands. One such demand is the advent of flexible electronics for wearable technology, medical applications, and biology-inspired mechanisms. This paper presents the design and performance characteristics of flexible electrohydrodynamic (EHD) pumps, based on EHD conduction pumping technology in macro- and mesoscales. Unlike mechanical pumps, EHD conduction pumps have no moving parts, can be easily adjusted to the microscale, and have been shown to generate and control the flow of refrigerants for electronics cooling applications. However, these pumping devices have only been previously tested in rigid configurations unsuitable for use with flexible electronics. In this work, for the first time, the net flow generated by flexible EHD conduction pumps is measured on a flat plane in various configurations. In this study, the results show that the flexible EHD conduction pumps are capable of generating significant flow velocities in all size scales considered in this study, with and without bending. This study also proves the viability of screen printing as a manufacturing method for these pumps. The selection of working fluid for EHD conduction pumping is also a topic of discussion. Novec Engineered Fluids have been a popular choice for EHD pumping; however, long-term testing has shown that some Novec fluids degrade over time.