Hydroxylammonium-nitrate-based monopropellant thrusters have been continuously researched as a replacement for conventional hydrazine thrusters. An ignition system using the discharge plasma of noble gas, called a discharge plasma system, has been proposed in substitution for the conventional solid catalysts. However, the combustion characteristics of the thruster are not well understood. The present study conducted firing tests of a 1-N-class thruster with the discharge plasma system under a vacuum condition. The objectives of the study were to experimentally evaluate the effects on the combustion characteristics of the combustion chamber characteristic length and the propellant injection method by the measurement of thrust and pressure. In this paper, the combustion characteristics of the monopropellant are discussed by considering the characteristic exhaust velocity efficiency and power consumption. In addition, the thruster lifetime is evaluated in terms of electrode degradation. With the non-atomized injector, a maximum thrust of 0.34 N is achieved at an argon mass flow rate of , a hydroxylammonium-nitrate-based monopropellant mass flow rate of , and a combustion chamber characteristic length of 508 mm. In addition, it was observed that a shorter combustion chamber characteristic length increased the characteristic exhaust efficiency. At an accumulated firing time of 1646 s, no effect of electrode degradation on the performance of the thruster was observed.
Combustion Characteristics of a Hydroxylammonium-Nitrate-Based Monopropellant Thruster with Discharge Plasma System
Journal of Propulsion and Power ; 34 , 4 ; 1052-1060
2018-02-21
9 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch