Far-field plume contamination and sputtering of the stationary plasma thruster

Randolph, Thomas; Pencil, Eric; Manzella, David

doi:10.2514/6.1994-2855

Cited by 24 publications

(19 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5 Results presented above showed that significant differences were observed between the BOL and EOL thruster tests. This section presents a review and improves upon the model development for sputtering and develops a new model for deposition to explain the observations in the BOL-thruster and EOL-thruster tests.…”

Section: Modeling Approach and Resultsmentioning

confidence: 67%

See 1 more Smart Citation

End-of-life Stationary Plasma Thruster far-field plume characterization

Pencil

Randolph²,

Manzella³

1996

32nd Joint Propulsion Conference and Exhibit

View full text Add to dashboard Cite

Section: Modeling Approach and Resultsmentioning

confidence: 67%

“…5 This linear approximation is less valid at ion energies below 100 eV as material sputtering thresholds are approached. A new expression was used to better fit the data.…”

Section: (5)mentioning

confidence: 98%

End-of-life Stationary Plasma Thruster far-field plume characterization

Pencil

Randolph²,

Manzella³

1996

32nd Joint Propulsion Conference and Exhibit

View full text Add to dashboard Cite

“…The GRC facility measured 4.6 m in diameter by 19.5 m in length and was able to maintain a 2:5 10 6 torr while the thruster was operational, and the TAC facility measured 2.4 m in diameter by 9.8 m in length and was able to maintain 4 10 6 torr while the thruster was operational. The probes used to take the measurements at TAC are described in [9], and the probes used to take the GRC data are described in [3]. A curve fit to the beam current-density data is also shown in Fig.…”

Section: A Current-density Modelmentioning

confidence: 99%

“…SS/L has developed and used a model to predict the impingement torques on spacecraft, allowing proper design of the spacecraft control operations [2,3]. The model was constructed to predict the impingement forces and torques on the spacecraft by the plume of the SPT-100 thrusters and was developed from fundamental physics principles and ground-test data.…”

Section: Introductionmentioning

confidence: 99%

Hall Thruster Plume Model for Spacecraft Impingement Torque: Development and Validation

Corey¹,

Snyder²,

Price³

et al. 2008

Journal of Spacecraft and Rockets

View full text Add to dashboard Cite

Space Systems/Loral has implemented the SPT-100 Hall effect thruster onto geostationary spacecraft for primary north-south station keeping, allowing substantial reductions in onboard propellant mass. Consideration of the spacecraft-thruster interactions is necessary when implementing electric propulsion thrusters onto communications satellites. Impingement of high-energy xenon ions on the spacecraft solar arrays and other large surfaces causes torques on the spacecraft that must be accounted for and controlled by the spacecraft control system. Space Systems/ Loral has developed and used a model to predict the impingement torques on the spacecraft, allowing proper design of the spacecraft control system. The impingement model is based on experimental current-density and ion-energy data taken during ground testing. Accommodation-coefficient values for the surfaces being investigated were based on values taken from open literature. Predictions from the plume model were compared with flight control-system data from two Russian-manufactured spacecraft. Modifications to the model were made for current density, based on correlation with the flight torque data. This paper will compare predictions based on this model with flight data from the Space Systems/Loral-manufactured Galaxy 28 and Thaicom 4 geosynchronous commercial spacecraft. Both spacecraft are equipped with an SPT-100 subsystem to perform north-south station keeping.Nomenclature C i = curve-fit coefficient e = elementary charge, 1:6 10 19 C F = force, N f " = current-density distribution function g = gravity constant at sea level, 9:8 m=s 2 j = current density, mA=cm 2 k i = curve-fit coefficient ke i = curve-fit coefficient m = mass, kg p = normal momentum flux, N=m 2 R = distance from the thruster exit plane to a point in space, m R cm = distance from the thruster to the spacecraft center of mass, m T = torque, N m u = current-weighted velocity, m=s v = ion velocity, m=s " = ion energy, eV = angle from the thruster centerline, deg n = normal momentum accommodation coefficient t = tangential momentum accommodation coefficient 0 = normal momentum accommodation coefficient, 0 = tangential momentum flux, N=m 2 = incident angle with respect to surface normal, deg

show abstract

“…Sputtering-induced erosion of antire ective solar cell cover glass coatings can degrade solar array performance by a few percent. 10 Erosion of solar cell interconnectscan increase the resistivityof the array circuitand reduce array performance. Whereas researchers have relied on sample exposure tests and computational modeling to predict the impact that plume impingement on spacecraft solar array material will have on spacecraft operations, these efforts have been hampered by facility effects and the need to make simplifying assumptions about the plume.…”

Section: Motivationmentioning

confidence: 99%

Near- and Far-Field Characterization of Stationary Plasma Thruster Plumes

Gallimore

2001

Journal of Spacecraft and Rockets

View full text Add to dashboard Cite

A comprehensive investigation of Hall thruster plume plasma ion energy distribution functions and ion charge state has been made on both ight-and laboratory-model engines. An energy analyzer, mass spectrometer, and E £ B probe were used to characterize Hall thruster plume ions. The results of this investigation show that the distribution function of the ion beam exhibits both Maxwellian and Druyvesteyn traits and that the Hall thruster plume contains a nontrivial amount of energetic, multiply charged particles that must be accounted for in modeling the erosion rate of solar array cover glass and interconnect material. Detection of these multiply charged ions by energy analyzers has been hampered in the past by charge exchange and elastic collisions. The high-energy tail seen in numerous energy analyzer data is thought to result from charge exchange and elastic collisions between singly and multiply charged ions and neutrals. The role of facility pressure was also investigated and was found to have an in uence mainly on the width of the ion energy distribution function. This pressure broadening is caused by elastic collisions between beam ions and background chamber gas particles. Nomenclaturecollector current, A n i = ion number density, m ¡3 q = elementary charge, C q I = charge state of ion r = position vector, m t = time, s u i = ion speed, m/s V i = beam ion acceleration potential, V v = ion velocity vector, m/s

show abstract

Far-field plume contamination and sputtering of the stationary plasma thruster

Cited by 24 publications

References 5 publications

End-of-life Stationary Plasma Thruster far-field plume characterization

End-of-life Stationary Plasma Thruster far-field plume characterization

Hall Thruster Plume Model for Spacecraft Impingement Torque: Development and Validation

Near- and Far-Field Characterization of Stationary Plasma Thruster Plumes

Contact Info

Product

Resources

About