Performance characteristics of electrohydrodynamic conduction pump in two-phase loops

Abstract

A direct-current electric field applied to dielectric fluids causes an imbalance in the dissociation-recombination reaction generating free space charges. Coulomb forces, resulting from the applied electric field, redistributes the generated charges resulting in the heterocharge layers in the vicinity of the electrodes. Proper design of the electrodes generates net axial How motion pumping the fluid. The electrohydrodynamic conduction pump is a novel device that pumps dielectric fluids using heterocharge layers formed by imposition of electrostatic fields. This paper investigates the performance characteristics of an electrohydrodynamic conduction pump in two-phase (liquid-vapor) thermal control loops. The electrohydrodynamic two-phase loop consists of an electrohydrodynamic conduction pump, condenser, evaporator, transport lines, and reservoir (accumulator). This paper presents the results of an extensive experimental matrix examining the operational performance of electrohydrodynamic-based two-phase loops. The testing programs employed two electrohydrodynamic-based loops, two electrohydrodynamic conduction pumps, and deaerated and commercial grade HFC-134a. The pumps and fluids were alternated between the loops to provide a degree of generality to the results. We report the generated pressure head, mass How rate, and pump power consumption as a function of refrigerant, applied voltage, and sink temperature. The experimental program lasted over two years. The experiments' results identified the effects of noncondensable gases, working fluid temperature, loop geometric parameter, and electrode design parameters to improve electrohydrodynamic conduction pump performance.