Difference between revisions of "ET Workshop Fall 2011 RAD"

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** limits radiation speed: ad-hoc
 
** limits radiation speed: ad-hoc
 
** also not very accurate
 
** also not very accurate
* Two-Moment-Scheme / Truncated moment
+
* Two-Moment-Scheme / Truncated moment scheme
** Start with Boltzmann equation
+
** start with Boltzmann equation
** Decompose into moments
+
** decompose into moments
** Truncate series
+
** truncate series
** close using some prescription
+
** close using some prescription (approximate the rest of the series)
 +
* Monte-Carlo

Revision as of 15:51, 2 November 2011

Possibilities

  • Leakage scheme
    • very ad-hoc
    • only mimicks loss due to radiation
  • Diffusion equation
    • accurate only when mean free path is really short
    • almost always implicit to avoid strong CFL limit
    • cheap, usually inaccurate
  • Flux limited diffusion
    • Diffusion + "trick" at lower optical depths
    • also simple, and has been used for supernovae simulations
    • unclear if working in GR
    • limits radiation speed: ad-hoc
    • also not very accurate
  • Two-Moment-Scheme / Truncated moment scheme
    • start with Boltzmann equation
    • decompose into moments
    • truncate series
    • close using some prescription (approximate the rest of the series)
  • Monte-Carlo