Thermal Control Utilizing an Electrohydrodynamic Conduction Pump in a Two-Phase Loop With High Heat Flux Source

The electric field applied in dielectric fluids causes an imbalance in the dissociation-recombination reaction generating free space charges. The generated charges are redistributed by the applied electric field, resulting in the heterocharge layers in the vicinity of the electrodes. Proper design of the electrodes generates net axial flow motion pumping the fluid. The electrohydrodynamic (EHD) conduction pump is a new device that pumps dielectric fluids utilizing heterocharge layers formed by imposition of electrostatic fields. This paper experimentally evaluates the performance of a two-phase (liquid-vapor) breadboard thermal control loop consisting of an EHD conduction pump, condenser, preheater, evaporator, transport lines, and reservoir (accumulator). This study is performed to address the feasibility of the EHD two-phase loop for thermal control of a laser equipment with high heat flux source. The generated pressure head and the maximum applicable heat flux are experimentally determined at various applied voltages and sink temperatures. Recovery from the evaporator dryout condition by increasing the applied voltage to the pump is also demonstrated. The performance of the EHD conduction pump in this study confirms that the EHD conduction pump can be used as a stand-alone system for high heat flux thermal control.