Electrohydrodynamic (EHD) pumping of single and two-phase media is attractivefor terrestrial and outer space applications since it is non-mechanical, lightweight, andinvolves no moving parts. In addition to pure pumping purposes, EHD pumps are alsoused for the enhancement of heat transfer, as an increase in mass transport oftentranslates to an augmentation of the heat transfer. Applications, for example, includetwo-phase heat exchangers, heat pipes, and capillary pumping loops.In this research, EHD induction pumping of liquid film in annular horizontal andvertical configurations is investigated. A non-dimensional analytical model accountingfor electric shear stress existing only at the liquid/vapor interface is developed forattraction and repulsion pumping modes. The effects of all involved parametersincluding the external load (i.e. pressure gradient) and gravitational force on the nondimensionalinterfacial velocity are presented. A non-dimensional stability analysis ofEHD induction pumping of liquid film in a vertical annular configuration in the presenceof external load for repulsion mode is carried out. A general non-dimensional stability criterion is presented. Stability maps are introduced allowing classification of pumpoperation as stable or unstable based on the input operating parameters.An advanced numerical model accounting for the charges induced throughout thebulk of the fluid due to the temperature gradient for EHD induction pumping of liquidfilm in a vertical annular configuration is derived. A non-dimensional parametric studyincluding the effects of external load is carried out for different entrance temperatureprofiles and in the presence of Joule heating.Finally, a non-dimensional theoretical model is developed to investigate and tounderstand the EHD conduction phenomenon in electrode geometries capable ofgenerating a net flow. It is shown that with minimal drag electrode design, the EHDconduction phenomenon is capable of providing a net flow. The theoretical model isfurther extended to study the effect of EHD conduction phenomenon for a two-phaseflow (i.e. a stratified liquid/ vapor medium). The numerical results presented confirm theconcept of liquid film net flow generation with the EHD conduction mechanism.
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