Measurements were made of a 40 cm ion-thruster plume as part of the single-string-integration-test (SSIT) activity of Phase I of the NASA’s Evolutionary Xenon Thruster (NEXT) project. The NEXT ion engine incorporates design improvements that extend NSTAR power levels and efficiencies. During SSIT, an engineering model (EM2) 40 cm engine was operated using an advanced xenon propellant system in ...

High thrust-to-power ratio on Hall-effect thrusters allows for more efficient thrust generation and better overall performance. It allows Hall-effect thrusters to perform more thrust-intensive maneuvers such as orbit raising, thus saving the mass of a second engine purely for those maneuvers. This paper presents the initial performance measurements of aHall-effect thruster using in-channel elec...

Preliminary results are presented, of measurements of thrust (T) and specific impulse (Isp), produced by a single emitter prototype colloid propulsion system. The development of the colloid thruster propulsion package at Stanford University is in preparation for flighttesting on a 20-kg university nanosatellite, to be launched in 2003. The half-kilogram Colloid Micro Thruster (CMT) package meas...

The thermal characterization test of NASA’s 12.5-kW Hall Effect Rocket with Magnetic Shielding has been completed. This thruster was developed to support a number of potential Solar Electric Propulsion Technology Demonstration Mission concepts, including the Asteroid Redirect Robotic Mission concept. As a part of the preparation for this characterization test, an infrared-based, non-contact the...

Hall current magnitude and spatial distribution are presented for the plasma discharge in the University of Michigan/Air Force Research Laboratory P5 5 kW laboratory-model Hall thruster. The data are calculated from direct, probe-based measurements of the electric field, static magnetic field, and charged particle number density. Thruster discharge voltage was fixed at 300 V and two current lev...

A new model of the plasma plume from Hall Effect Thrusters (HET's) is presented. The model includes the self-expansion of the main beam by density gradient electric fields, lowenergy ions produced by resonant charge exchange between beam ions and neutral atoms (ambient and thruster-induced), and angle-dependent elastic scattering of beam ions off neutral atoms. The variation of radial velocitie...

Performance measurements have been obtained of a novel propulsion concept called the Halo thruster under developmentwithin theUniversity of Surrey. TheHalo thruster, a type of cusped-field thrusterwith close similarity to the cylindrical Hall thruster, is motivated by the need for low-power and low-cost electric propulsion for the small satellite sector. Two versions of the device are investiga...

The temporal characteristics of the Xe ion axial Velocity Distribution Function (VDF) were recorded in the course of low-frequency discharge current oscillations (∼ 14kHz) of the 5 kW-class PPSrX000 Hall thruster. The evolution in time of the ion axial velocity component is monitored by means of a laser induced fluorescence diagnostic tool with a time resolution of 100ns. As the number of fluor...

Detailed direct simulation Monte Carlo/particle-in-cell simulations involving the interaction of spacecraft thruster plumes with the rarefied ambient ionosphere are presented for steady thruster firings in low Earth orbit (LEO). A nominal mass flow rate is used to prescribe the rocket exit conditions of a neutral propellant species for use in the simulations. The charge exchange interactions of...

Theoperation andperformance of amicro-Hall thruster are characterized.The thruster is coaxial in design,with a 0.5 mm channel width and 4 mm outer diameter. The magnetic circuit includes a samarium cobalt permanent magnet generating approximately 0.7 T at the exit plane and 1 T inside the channel. Operation with a commercial hollow cathode neutralizer is achieved in the 10–40 W power range with...