Resistojets and Arcjets

Abstract

The simplest forms of electrically augmented propulsion for spacecraft are resistance‐heated and arc‐heated thrusters, generally called resistojets and arcjets, respectively. As with all forms of electric propulsion, electric energy added from the spacecraft increases the specific impulse over that achievable with a chemical reaction and expansion through a nozzle. With electrothermal devices, the added energy is imparted to the propellant as thermal energy. In the specific case of the resistojet, energy is added to the propellant with a resistance heater. In the case of an arcjet, an arc is drawn directly through the propellant between a cathode and an anode. The augmented specific impulse is limited by the maximum temperature tolerable by key components over the necessary life of the thruster. The maximum thrust as a function of input electrical power is limited by the efficiency with which the electrical energy is coupled into and contained within the flow and by the efficiency with which the flow enthalpy is converted to axial kinetic energy in the expansion. Resistojets and arcjets have been in development since the late 1950s and have been used on well over 200 spacecraft. This chapter describes the basic construction of these devices, illustrates relationships governing their performance, and surveys the performance demonstrated by a range of laboratory and flight qualified models.

Ion thrusters for electric propulsion: Scientific issues developing a niche technology into a game changer

“…104 We do not provide a detailed description of all individual thruster types here and refer the reader-to beside the already mentioned-to other relevant literature. 41,[105][106][107][108][109][110][111][112] All three main thruster types have in common that electrical energy is converted into kinetic energy of the exhausted particles to generate or increase thrust. This energy conversion process differs in efficiency for the three types and is also very different in terms of the complexity of the technical implementation.…”