[Mesa-users] Relaxing angle-averaged model from hydro simulation
Manos Chatzopoulos
chatzopoulos at phys.lsu.edu
Tue Feb 6 18:24:38 EST 2018
Pablo,
Thanks for the very helpful and kind response! I will certainly look
forward to trying out your suggestions. In the meantime, here is the
terminal output I get when I include angular momentum relaxation:
-------
avg remaining difference, lambda
0.0000000000000000D+00 1.0000000000000000D+00
relax_initial_angular_momentum
relax_angular_momentum: max_steps_to_use 1000
failed in mixing angular momentum
retry log10(dt/yr), log10(dt), retry_factor 1 1
-9.602060 -2.102948 0.500000
hydro_newton_step failed to accept
retry log10(dt/yr), log10(dt), retry_factor 2 1
-9.903090 -2.403978 0.500000
have reached retry limit so now backup
failed in mixing angular momentum
retry log10(dt/yr), log10(dt), retry_factor 1 1
-10.204120 -2.705008 0.500000
hydro_newton_step failed to accept
retry log10(dt/yr), log10(dt), retry_factor 2 1
-10.505150 -3.006038 0.500000
have reached retry limit so now backup
hydro_newton_step failed to accept
retry log10(dt/yr), log10(dt), retry_factor 1 1
-11.408240 -3.909128 0.500000
hydro_newton_step failed to accept
retry log10(dt/yr), log10(dt), retry_factor 2 1
-11.709270 -4.210158 0.500000
have reached retry limit so now backup
hydro_newton_step failed to accept
retry log10(dt/yr), log10(dt), retry_factor 1 1
-13.214420 -5.715308 0.500000
hydro_newton_step failed to accept
retry log10(dt/yr), log10(dt), retry_factor 2 1
-13.515450 -6.016338 0.500000
have reached retry limit so now backup
dt
3.0096197113037110D-08
min_timestep_limit
9.9999999999999995D-07
stopping because of problems dt < min_timestep_limit
do_relax_initial_angular_momentum ierr -1
do_star_job_controls_after ierr -1
before_evolve_loop ierr -1
---------
And here it is when I exclude it:
avg relative error, dt/secyer, model_number 0.73839791983438141
4.6050354628669335E-014 712
hydro_newton_step failed to accept
retry log10(dt/yr), log10(dt), retry_factor 1 713
-13.938827 -6.439715 0.500000
dt
7.2663199909396781D-07
min_timestep_limit
9.9999999999999995D-07
stopping because of problems dt < min_timestep_limit
do_relax_initial_entropy ierr -1
do_star_job_controls_after ierr -1
before_evolve_loop ierr -1
--------
Cheers, and thanks again for the valuable input!
Manos
On 2/6/18 5:16 PM, Pablo Marchant wrote:
> Hi Manos,
>
> can you share your terminal output to get an idea?
>
> we are doing some work to stabilize the relax routines, can't give you
> an ETA on that though. In particular with rotation I found that the
> current implementation of the calculation of FP and FT (the correction
> factors to the pressure and temperature equations) can experience some
> large changes which make convergence hard.
>
> I have some unfinished work now trying to integrate these factors for
> the case of a point mass Roche potential. This is a good approximation
> for most stellar purposes, and it allows constructing a simple fit to
> the integrated values rather than having to recompute it in MESA.
> Attached is a simple example of this implementation, it's mostly using
> a couple of by-eye-fits I made (see the attached plot showing the
> factors as a function of the volume equivalent radius). Can you try
> this out and see if it improves things at all? Goes in star/private/.
> Not promising anything though.
>
> Another option is to increase the steps for relaxation, for instance:
>
> num_steps_to_relax_composition = 300
>
> in star_job
>
> Cheers
>
> On Tue, Feb 6, 2018 at 4:23 PM, Manos Chatzopoulos
> <chatzopoulos at phys.lsu.edu <mailto:chatzopoulos at phys.lsu.edu>> wrote:
>
> Dear mesa-users,
>
> We are using our 3D hydro code (OctoTiger) to simulate the stellar
> merger of an 1Msun star within the envelope of a larger (~14 Msun)
> star. We then extract the angle-averaged data in the format
> required by the MESA (v. 10108) relaxation routines (as set in the
> relax_composition_j_entropy test_suite setup and described in the
> star/defaults/star_job.defaults). I attach plots of our
> entropy_new.dat, angular_momentum_new.dat and composition_new.dat
> inputs showing the models we import into MESA starting with the
> inlist_relax_composition_j_entropy (attached). I also attach *png
> plots showing comparison between these profiles (only for H/He in
> composition) and the original profiles used in the test_suite
> problem. As you can see we are setting the mass of the desired
> relaxed model equal to the mass coming out from our simulation.
>
> We are having issues getting a converged/relaxed model, especially
> when we turn on relaxation for the angular momentum profile (Which
> we need, ultimately). Any help/input would be greatly appreciated
> on how to move forward.
>
> Best regards,
>
> --
> Dr. Manos Chatzopoulos
> Assistant Professor
> Department of Physics & Astronomy
> Louisiana State University
> Nicholson #275
> Office # 225-578-2907
> Baton Rouge, LA 70803
> United States of America
> http://www.lsu.edu/physics/people/faculty/chatzopoulos.php
> <http://www.lsu.edu/physics/people/faculty/chatzopoulos.php>
>
>
> _______________________________________________
> mesa-users at lists.mesastar.org <mailto:mesa-users at lists.mesastar.org>
> https://lists.mesastar.org/mailman/listinfo/mesa-users
> <https://lists.mesastar.org/mailman/listinfo/mesa-users>
>
>
>
>
>
> --
> Pablo Marchant Campos
> M.Sc on Astrophysics, Universidad Católica de Chile
> PhD on Astrophysics, Argelander-Institut für Astronomie, Universität Bonn
--
Dr. Manos Chatzopoulos
Assistant Professor
Department of Physics & Astronomy
Louisiana State University
Nicholson #275
Office # 225-578-2907
Baton Rouge, LA 70803
United States of America
http://www.lsu.edu/physics/people/faculty/chatzopoulos.php
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.mesastar.org/pipermail/mesa-users/attachments/20180206/0a42e295/attachment.html>
More information about the Mesa-users
mailing list