Ionic Liquid Dual-Mode Spacecraft Propulsion Assessment

摘要

Analytical and numerical investigations of the performance of a series of potential dual-mode propulsion systemsnusing ionic liquids are presented. A comparison of the predicted specific impulse of ionic liquids with hydrazine andnunsymmetrical dimethylhydrazine shows that ionic liquid fuels have a 3–12% lower specific impulse when pairednwith a nitrogen tetroxide oxidizer. However, when paired with hydroxylammonium nitrate oxidizer, the specificnimpulse of the ionic liquids is 1–4%lower than that of hydrazine and unsymmetrical dimethylhydrazine paired withnnitrogen tetroxide. Analytical investigation of an electrospray electric propulsion systemshows that ion extraction innthe pure ion regime provides a very high specific impulse, outside the optimum range for potential missions. Resultsnsuggest a deceleration grid, a lower ion fraction, or emission of higher solvated states is required. Analysis of a dual-nmode ionic-liquid-propelled spacecraft shows that the electric propulsion component determines the overallnfeasibility comparedwith current technology.Results indicate that the specific power for an ionic liquid electrospraynsystemmust be at least 15 = in order for a dual-mode ionic liquid systemto compete with traditional hydrazinenand Hall thruster technology.