More technical details can be found in the associated conference paper: Heavy-Cargo Mars Mission Using Near-Term Technology.
The lab came back from Atlanta following a successful International Electric Propulsion Conference! Will Coogan, Chris Wordingham, and Pierre-Yves Taunay published three conference articles pertaining to applied-field MPD thrusters, theory of hollow cathodes, and a mission plan to Mars using near-term technology:
Will Coogan finished installing the Argon Lorentz Force Accelerator (ALFA) and obtained some thrust measurements over the summer. He previously operated the thruster at 100 A, and recently increased the discharge current to 220 A, as shown below.
Congratulations to our two seniors Jack Hollingsworth and Josh Umansky-Castro for completing their degree!
Both of them worked in the steel tank, on Lorentz Force Accelerators. Josh designed and built a video pod that would withstand the extreme environment (vacuum, plasma, high-temperature, lithium vapor) in the tank during operation of the Lithium Lorentz Force Accelerator (LiLFA). The video feed will provide high-quality video of the lithium MPD discharge. Jack performed structural and thermal FEM analysis of the Argon Lorentz Force Accelerator (ALFA), and manufactured the ALFA. He also performed evaporation measurements of the lanthanum hexaboride insert in the graphite hollow cathode after operating the MPD thruster.
Their senior thesis may be found here:
- Jack Hollingsworth - A Graphite Orificed Hollow Cathode for an Argon Magnetoplasmadynamic Thruster
- Josh Umansky-Castro - Extreme Environment Video Diagnostic for a Lithium Lorentz Force Accelerator
The brand-new Argon Lorentz Force Accelerator (ALFA) is done being fabricated! This thruster was designed and built by Jack Hollingsworth and Will Coogan for use in the facilities presently used by the LiLFA. This is the first magnetoplasmadynamic thruster to make use of a LaB6 orificed cathode. The performance of this thruster will be reported at the 2017 International Electric Propulsion Conference.
The dimensions of the graphite thruster electrodes are matched to those of the tungsten LiLFA. We contoured the nozzle to match the shape of the applied magnetic field. We anticipate running at power levels up to 30 kW.
Photo credit: Josh Umansky-Castro, Diagram: Will Coogan
|Design of a High-energy, Two-stage Pulsed Plasma Thruster||38th AIAA/ASME/SAE/ASEE Joint Propulsion Conference||2002||Thomas Markusic, Y. Thio, J. Cassibry|
|The adverse effect of perpendicular ion drift flow on cylindrical triple probe electron temperature measurements||Review of Scientific Instruments||1994||Dennis Tilley, Alec Gallimore, Arnold Kelly, Robert Jahn|
|Anode Power Deposition in Magnetoplasmadynamic Thrusters||Journal of Propulsion and Power||1993||Alec Gallimore, Arnold Kelly, Robert Jahn|
|Energy Deposition in Low-Power Coaxial Plasma Thrusters||Journal of Propulsion||1991||Roger Myers, Arnold Kelly, Robert Jahn|
|Cathode Phenomena in Low-Power Magnetoplasmadynamic Thruster||Journal of Propulsion||1991||Roger Myers, N. Suzuki, Arnold Kelly, Robert Jahn|
|Assymetric Discharge Patterns in the MPD Thruster||Master's Thesis||1990||W. Hoskins|
|Measurement of MPD Thruster Erosion Using Surface Layer Activation||Journal of Propulsion||1987||Jay Polk, Woldemar von Jaskowsky, Arnold Kelly, Robert Jahn|
|MPD Thruster Performance: Propellant Distribution and Species Effects||Journal of Propulsion||1986||D. Merfeld, Arnold Kelly, Robert Jahn|
|Measured Performance of a Multimegawatt MPD Thruster||Journal of Spacecraft||1983||Rodney Burton, Kenn Clark, Robert Jahn|
|Magnetoplasmadynamic Channel Flow for Design of Coaxial MPD Thrusters||Ph.D. Dissertation||1982||David King|
|Erosion Measurements on Quasisteady Magnetoplasmadynamic Thrusters||Journal of Spacecraft||1982||R. Rowe, Woldemar von Jaskowsky, Kenn Clark, Robert Jahn|
|Recombination Lasing in a Magnetoplasmadynamic Arcjet||Journal of Applied Physics||1980||E. Campbell, Robert Jahn, Woldemar von Jaskowsky, Kenn Clark|
|Physical Processes in Hollow Cathodes||AIAA Journal||1977||M. Krishnan, Robert Jahn, Woldemar von Jaskowsky, Kenn Clark|
|Flowfield Characteristics and Performance Limitations of Quasi-Steady Magnetoplasmadynamic Accelerators||AIAA Journal||1976||M. Boyle, Kenn Clark, Robert Jahn|
|Exhaust Plume Structure in a Quasi-Steady MPD Accelerator||AIAA Journal||1974||Adam Bruckner, Robert Jahn|
|Anode Phenomena in High-Current Accelerators||AIAA Journal||1972||Ronald Oberth, Robert Jahn|
|Cathode Region of a Quasi-Steady MPD Arcjet||AIAA Journal||1971||Peter Turchi, Robert Jahn|
|Acceleration Patterns in Quasi-Steady MPD Arcs||AIAA Journal||1971||Robert Jahn, Kenn Clark, Ronald Oberth, Peter Turchi|
|Current Pattern and Gas Flow Stabilization in Pulsed Plasma Accelerators||AIAA Journal||1970||A. Eckbreth, Robert Jahn|
|Energy Transfer from a Pulse Network to a Propagating Current Sheet||AIAA Journal||1970||Paul Wilbur, Robert Jahn|
|Quasi-Steady Plasma Acceleration||AIAA Journal||1970||Kenn Clark, Robert Jahn|
|Pressure Distribution in the Structure of a Propagating Current Sheet||Physics of Fluids||1970||Thomas York, Robert Jahn|
|Electron Beam from a Magnetoplasmadynamic Arc||Physics of Fluids||1969||Adriano Ducati, Robert Jahn|
|Ion density and current distributions in a propagating current sheet, determined by microwave reflection technique||Journal of Plasma Physics||1969||W. Ellis, Robert Jahn|
|Physics of Electric Propulsion||Book||1968||Robert Jahn|
|Current Pattern Stabilization in Pulsed Plasma Accelerators||AIAA Journal||1968||A. Eckbreth, Kenn Clark, Robert Jahn|
|The Magnetoplasmadynamic Arcjet||Astronautica Acta||1967||Kenn Clark, Robert Jahn|
|A Large Dielectric Vacuum Facility||AIAA Journal||1966||Robert Jahn, Kenn Clark|
|Dynamic Efficiency of Pulsed Plasma Accelerators||AIAA Journal||1965||Neville Black, Robert Jahn|
|Ejection of a Pinched Plasma from an Axial Orifice||AIAA Journal||1965||Robert Jahn, Woldemar von Jaskowsky, Rodney Burton|
|Miniature Rogowski Coil Probes for Direct Measurement of Current Density Distributions in Transient Plasmas||Review of Scientific Instruments||1965||Edward Wright, Robert Jahn|
|Gas-Triggered Pinch Discharge Switch||Review of Scientific Instruments||1965||Robert Jahn, Woldemar von Jaskowsky, A. Casini|
|Current Distributions in Large-Radius Pinch Discharges||AIAA Journal||1964||Robert Jahn, Woldemar von Jaskowsky|
|Initial Ionization Rates in Shock-Heated Argon, Krypton, and Xenon||Physics of Fluids||1964||Kenneth Harwell, Robert Jahn|
|Gas-Triggered Inverse Pinch Switch||Review of Scientific Instruments||1963||Robert Jahn, Woldemar von Jaskowsky, A. Casini|
|Structure of a Large-Radius Pinch Discharge||AIAA Journal||1963||Robert Jahn, Woldemar von Jaskowsky|
|Microwave probing of ionized-gas flows||Physics of Fluids||1962||Robert Jahn|