Christopher Young
- Academic Institution: Stanford University
- Program Year: 2
- Practicum(s):
Lawrence Livermore National Laboratory (2012) - Degree(s):
B.S. Engineering Physics, Stanford University, 2010 - Field of Study: Plasma Physics / Thermosciences
- Academic Advisor: Mark Cappelli
Summary of Research:
My research at Stanford has been to experimentally characterize and simulate a cylindrical plasma accelerator used by small satellites for efficient propulsion once in orbit. Electrons emitted from an external cathode either migrate into the main channel to ionize passing propellant molecules or exit with the ions in the plume, maintaining charge neutrality. Resolving the details of electron transport throughout the thruster’s complicated electric and magnetic field geometries will improve its performance and enhance our understanding of the basic plasma physics at the heart of such devices.One tool for studying electron transport is a single particle trajectory simulation that tracks electrons along virtual trips throughout the thruster under the influence of the EM fields and various collisional processes. The code incorporates experimental plasma potential data obtained with an emissive probe. Another study seeks to experimentally investigate magnetized plasma sheaths and their influence on electron and ion flow near the channel walls – particles striking the wall cause erosion and device inefficiency. This experiment utilizes time-independent laser induced fluorescence techniques to measure ion velocities via an observed Doppler shift and has broader application to magnetic plasma confinement.
While a summer student in the 2011 Lawrence Livermore National Laboratory (LLNL) High Energy Density Physics program, my research expanded into inertial confinement fusion with a project studying surrogate National Ignition Facility targets with the radiation-hydrodynamics code HYDRA. Back at LLNL for my SSGF practicum in the summer of 2012, I developed a plasma simulation using the Kinetic Finite Mass (KFM) Method. Electron and ion mass in the domain is partitioned into “packets” that evolve over time under the action of forces. The KFM method can be applied to a variety of problems, and is especially suited to resolving steep density gradients. The code is still being improved to tackle more complex plasma phenomena.
Publications:
Young, C. and Cappelli, M. "Electron Transport Via Collisional Mechanisms in a Cusped Plasma Accelerator." Bulletin of the 65th Annual Gaseous Electronics Conference. Vol. 57, No. 8 (2012)MacDonald, N.A., Young, C.V., Cappelli, M.A., Hargus Jr., W.A. "Ion Velocity and Plasma Potential Measurements of a Diverging Cusped Field Thruster," J. Appl. Phys. 111, 093303 (2012)
Young, C. and Meezan, N. "Design of High-Performance Symmetry Capsule Implosions." Bulletin of the 53rd Meeting of the American Physical Society Division of Plasma Physics. Vol. 56, No. 16 (2011)
Young, C. and Cappelli, M. "Experimental and Computational Investigation of a Plasma Ion Accelerator with Multiple Magnetic Field Cusps." Bulletin of the 64th Annual Gaseous Electronics Conference. Vol. 56, No. 15 (2011)
Young, C.V. "The Stanford Diverging Cusped Field Thruster: Design, Construction, and Initial Testing," Undergraduate Honors Thesis, Engineering Physics, Stanford University (2010)
Young, C.V., Smith, A.W., Cappelli, M.A. "Preliminary Characterization of a Diverging Cusped Field (DCF) Thruster," Proceedings of the 31st International Electric Propulsion Conference (IEPC), University of Michigan, Ann Arbor, MI. (2009)
Awards:
DOE NNSA Stewardship Science Graduate Fellow, 2011NSF Graduate Research Fellowship Awardee, Declined for DOE NNSA SSGF, 2011
Stanford Graduate Fellowship, 2010
Firestone Medal: Excellence in Undergraduate Research, 2010
Tau Beta Pi: National Engineering Honor Society, Member since 2009
Stanford University President's Award: Academic Excellence in the Freshman Year, 2007
