Changes between Version 1 and Version 2 of AthenaDocsUGConduct


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Timestamp:
06/24/10 09:53:31 (4 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.