Single- and Two-Phase Flow in Microchannels With Heat Transfer and Driven by an EHD Conduction Pump

Microchannels have well-known applications in cooling because of their ability to handle large quantities of heat from small areas. Electrohydrodynamic (EHD) conduction pumping at the micro-scale has previously been demonstrated to effectively pump dielectric liquids through adiabatic microchannels by using electrodes that are flushed against the walls of the channel. In this study, an EHD micropump is used to pump liquid within a two-phase loop that contains a microchannel evaporator. Additional EHD electrodes are embedded within the evaporator, which can be energized separately from the adiabatic pump. The enhancement effect of these embedded electrodes on the heat transport process in the micro-evaporator and on the two-phase loop system is characterized. Single- and two-phase heat transfer regimes are both studied and the effect of applied voltage and heat flux are considered on the overall flow rate and the wall temperature of the microchannel.