Characterization of discharge uniformity and performance via stimulated beam extraction of a 65 cm annular ion engine

The annular ion engine concept consists of a cylindrical ion thruster with a centrally located stalk that provides increased anode area. The increased electron collection area allows for increased discharge plasma current, and thus high power operation. The central stalk also provides support for the ion optics, allowing for larger beam area and scale up potential. Discharge performance of a 42 cm annular ion engine has previously been studied. Here, the discharge uniformity of a 65 cm annular ion engine during simulated beam extraction is assessed using three diagnostics: Faraday probes, Langmuir probes, and a fast camera. The percent uniformity was found to vary from 89.8% to 97.4% for discharge powers under 1.5 kW. The data presented herein demonstrates the feasibility of scalability of the annular ion engine. PhD candidate, Nuclear Engineering and Radiological Sciences, 2355 Bonisteel Blvd., AIAA student member Professor, Nuclear Engineering and Radiological Sciences, 2355 Bonisteel Blvd., AIAA member Senior Technologist, Power and In-Space propulsion Division, 2100 Brookpark Rd./MS 301-3, AIAA senior member Research Engineer, Propulsion and Propellants Branch, 21000 Brookpark Rd./MS 301-3, AIAA member Member of Technical Sta↵, Space Materials Laboratory, P.O. Box 92957 M2-341, AIAA member Senior Scientist, Space Materials Laboratory, P.O. Box 92957 M2-341, AIAA senior member