John Santarius and Greg Moses

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UW First-WallThreat Spectra Calculations
John Santarius and Greg Moses University of
Wisconsin HAPL Project Meeting General
Atomics August 8-9, 2006
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In the Present Approach, Ghost Zones Move
through Hydro Zones

• Ghost zones interact with zone boundaries, but
  only as they pass through them.

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Zone Flow Logic

• Check all zones for ratio of kl to dr in both
  directions.
• l is mean free path.
• k is a chosen multiplier, typically 3.
• If klltdr for a zone, use pure hydro.
• If kl³dr for a zone, move through next zone in u
  direction, depositing momentum and energy, for
  time step dttime of next zone boundary contact.
• Adjust radii of zones.
• Repeat process until dt is reached or no zones
  satisfy kl³dr.
• Renumber zones, if necessary.

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Vector kz Indicates Detachment Status of Zone
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Hydro Subvector Components
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Ghost Subvector Components
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Lagrangian Zone Mass Density Falls Steeply
Hydro zones
Main shock
Ghost zones
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Lagrangian Zone Velocity Evolutionfor Mean Free
Paths gt Shock Thickness
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Lagrangian Zone Mass Evolutionfor Mean Free
Paths gt Shock Thickness
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Status and Summary

• Have made progress with Mathematica code for
  analysing velocity transfer between hydro and
  long mean-free path zones.
• Some debugging remains to be done.
• Should give a reasonable qualitative picture of
  the effect of long mean free paths on the ion
  threat spectra.

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Back Pocket
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DT Core, DT-CH Shock, and CH-Au Shock Will
Exemplify the Issues
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At 34.592 ns, the DT-CH Shock Thickness
andIncoming Ion Mean Free Paths Become Comparable