Radiation transport with lightsabers

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Radiation transportwith lightsabers

• Axel Brandenburg (Nordita, Stockholm)

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PencilCode

• Started in Sept. 2001 with Wolfgang Dobler
• High order (6th order in space, 3rd order in
  time)
• Cache memory efficient
• MPI, can run PacxMPI (across countries!)
• Maintained/developed by 40 people (SVN)
• Automatic validation (over night or any time)
• Max resolution so far 10243 , 256 procs

• Isotropic turbulence
• MHD, passive scl, CR
• Stratified layers
• Convection, radiation
• Shearing box
• MRI, dust, interstellar
• Self-gravity
• Sphere embedded in box
• Fully convective stars
• geodynamo
• Other applications
• Homochirality
• Spherical coordinates

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Online data reduction and visualization
non-helically forced turbulence
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Scalars on periphery of the box
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Vorticity and Density
See poster by Tobi Heinemann on density wave
excitation!
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Volume renderingInterlockedflux rings
Standard routines Dont work above 5123
meshpoints.
Kerr Brandenburg (1999, Phys. Rev. Lett.)
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Volume rendering

• Want to see everything in the volume
• Forground should cover background stuff
• More than just one field
• Different colors

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Mutual obscuration as with lightsabers
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Transfer equation parallelization
Processors
Analytic Solution
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The Transfer Equation Parallelization
Processors
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The Transfer Equation Parallelization
Processors
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Source function opacity
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Different colors/frequencies?
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Color table
255
240
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Movie
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Pictures