Page 15 - Progress minimizing fast-ion charge-exchange loss associated with gas injection on C-2W

Neutral transport modeled using DEGAS21,2
• Kinetic neutral transport using Monte-Carlo sampling
• Includes comprehensive reactions:
• D2 dissociation, ionization, dissociative ionization
• D2+ dissociation, dissociative ionization, dissociative recombination
• D+ + D, D2 + D charge-exchange and elastic scattering
• Detailed wall treatment:
• Particle reflection from walls using TRIM data for Fe • Molecular desorption from walls to model recycling
• Evaluated with multiple plasma backgrounds
• Results with low-ne mirror plasma and example FRC plasma shown.
• Various gas injection locations:
• midplane, mirror throat radial, mirror throat tangential (27 cm impact parameter)
• Calculated ionization and neutral distributions • nD,eff =. nD + 2nD2 + nD2+
• Normalized for a 0.5 A D2 gas puff source
• Ionization efficiency (Si,T/): total ionization rate (Si,T) / fueling rate ()
1Stotler, D., Karney, C., Contributions to Plasma Physics 34 2 1994 2http://w3.pppl.gov/degas2
Presenter: Erik Granstedt 12