Changes between Version 1 and Version 2 of AthenaDocsUGConduct


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Timestamp:
Jun 24, 2010 9:53:31 AM (7 years ago)
Author:
jmstone
Comment:

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  • AthenaDocsUGConduct

    v1 v2  
    22
    33'''[wiki:AthenaDocs Documentation]/[wiki:AthenaDocsUG UserGuide]/Thermal Conduction'''
     4
     5Both isotropic and anisotropic thermal conduction can be added.  In either case,
     6configure the code with
     7{{{
     8% configure --enable-conduction
     9}}}
     10Both are added at first-order via operator splitting.
     11
     12The update is explicit in time, so that a very restrictive CFL constraint on the time step will be used.
     13
     14== Isotropic thermal conduction ==
     15
     16Enable by setting a value for the coefficient of conduction {{{kappa_iso}}} in the problem generator.  For example, to read a value
     17from the {{{<problem>}}} block in the input file, or to set a default value of zero if a value is not specified in the input file, add the line
     18{{{
     19  kappa_iso = par_getd_def("problem","kappa_iso",0.0);
     20}}}
     21anywhere in the problem generator.
     22If the code detects {{{kappa_iso > 0}}}, then thermal conduction will be applied.  Currently {{{kappa_iso}}} must be a constant.
     23
     24== Anisotropic thermal conduction ==
     25
     26In this case, the heat flux is parallel to the magnetic field lines.  '''''MHD must be enabled'''''
     27to use anisotropic thermal conduction.
     28
     29Enable by setting a value for the coefficient of parallel conduction {{{kappa_aniso}}} in the problem generator.  For example, to read a value
     30from the {{{<problem>}}} block in the input file, or to set a default value of zero if a value is not specified in the input file, add the line
     31{{{
     32  kappa_aniso = par_getd_def("problem",kappa_aniso",0.0);
     33}}}
     34anywhere in the problem generator.
     35If the code detects {{{kappa_aniso > 0}}}, then thermal conduction will be added.  Currently {{{kappa_aniso}}} must be a constant.
     36
     37To add ''both'' non-zero parallel and isotropic thermal conduction, simply set values for both {{{kappa_iso}}} and {{{kappa_aniso}}} in the
     38problem generator.
     39
     40If both {{{kappa_iso}}} and {{{kappa_aniso}}} are zero, and conduction is enabled, the code will terminate with an error message.