Re: mesa-users] how to heat the envelope of star

[Bill P. <pa...@ki...>]

On Sep 6, 2010, at 2:58 AM, xianfei zhang wrote:

> Dear Bill,
> I am trying to use MESA on some special stages of stellar evolution. 
> I want to heat the envelope of the star or to add some high temperature/entropy matters on it surface.
> I don't know each packages of MESA in detail, could you please tell me which variable can used for this or do you have an introduction for all variables?
> Dose 'extra_power_source' or 'T_function1' works for this? How to use it? (I just want to heat part of star not whole star)
> Thank you very much.
> Kind regards,
> Xianfei  

Hi,

Please install the current release, which as of 5 minutes ago, is 2647.

In response to your request, there are some new controls concerning extra heating.

These can be set in the &star_job section of your inlist file.


         
         relax_eps_extra = .false. ! if true, add an extra power source
         relax_eps_extra_min_steps = 0 ! use at least this many steps to change the parameters
         ! extra power is added according to the relative mass coordinate q
         new_qlow_for_extra_eps = 0 ! min q for extra eps
         new_qpeak_for_extra_eps = 0 ! q between min and max
         new_qhigh_for_extra_eps = 0 ! max q for extra eps
         new_extra_eps_at_qlow = 0 ! power at qlow as ergs/g/s
         new_extra_eps_at_qpeak = 0 ! power at qpeak
         new_extra_eps_at_qhigh = 0 ! power at qhigh
         ! interpolate extra_eps linearly in q between these 3 points


If the code has trouble converging after you have changed eps_extra, you may need to
turn it on at part strength and let the code run for ten or twenty steps to stabilize before
repeating the process until you reach full strength.


Cheers,
Bill