A High Power Ion Thruster Plume Model

A 2-D axisymmetric plume model of a 30-cm ion engine, operating at >20kW of jet power is presented. The model accounts for the main ion components expected to be present in the thruster plume, namely main beam ions and ion products from ion-neutral scattering. Main beam ions are found within ~30 deg of the axis of symmetry, and have energies in excess of 3000 eV and peak densities in the order of 10 15 m -3 near the thruster exit. Ions that undergo charge exchange with neutrals are expelled radially from the main beam by electric forces due to their low energies ( 70 deg). Ions that are elastically scattered retain a major portion of their initial kinetic energy (100-3000 eV) and are found with peak densities in the order of 10 12 m -3 and populate the complete range of plume angles; however, for issues associated with spacecraft sputtering their presence between angles of 30 to 70 deg is most critical.

[1]  J. Polk,et al.  An overview of the Nuclear Electric Xenon Ion System (NEXIS) program , 2003 .

[2]  S. Oleson,et al.  Electric Propulsion for Project Prometheus , 2003 .

[3]  Michael J. Patterson,et al.  Next: NASA's Evolutionary Xenon Thruster development status , 2003 .

[4]  David H. Manzella,et al.  Plume Modeling of Stationary Plasma Thrusters and Interactions with the Express-A Spacecraft , 2002 .

[5]  Michael J. Patterson,et al.  NEXT: NASA's Evolutionary Xenon Thruster , 2002 .

[6]  Ioannis G. Mikellides,et al.  ASSESSMENT OF SPACECRAFT SYSTEMS INTEGRATION USING THE ELECTRIC PROPULSION INTERACTIONS CODE (EPIC) , 2002 .

[7]  Michael J. Patterson,et al.  Demonstration of the NSTAR ion propulsion system on the Deep Space One mission , 2001 .

[8]  Ioannis G. Mikellides,et al.  A Hall effect thruster plume model including large-angle elastic scattering , 2001 .

[9]  D. A. King,et al.  Ion flux, energy, and charge-state measurements for the BPT-4000 Hall thruster , 2001 .

[10]  David T. Young,et al.  Ion Engine Generated Charge Exchange Environment: Comparison Between NSTAR Flight Data and Numerical Simulations , 2000 .

[11]  R. Dressler,et al.  Ion Dynamics in Hall Effect and Ion Thrusters: Xe' + Xe Symmetric Charge , 2000 .

[12]  Daniel E. Hastings,et al.  Numerical study of spacecraft contamination and interactions by ion-thruster effluents , 1996 .

[13]  Ioannis G. Mikellides,et al.  Elastic scattering of ions in electrostatic thruster plumes , 2005 .

[14]  M. J. Mandell,et al.  A Hall-Effect Thruster Plume and Spacecraft Interactions Modeling Package , 2001 .

[15]  M. Keidar,et al.  Particle Simulations of a Hall Thruster Plume , 2000 .