Changes between Version 11 and Version 12 of u/lchamandy/2017-04-17


Ignore:
Timestamp:
04/17/17 13:43:53 (9 years ago)
Author:
Luke
Comment:

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  • u/lchamandy/2017-04-17

    v11 v12  
    288288[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/rho2dv_fix_sph_tau1e5.gif 2d density and velocity]
    289289
     290'''Comparison with (b) on left and (e) on right'''\\
     291(i) Constant ambient pressure and density\\
     292[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/rho2d_fix_reflec_tau1e5.gif 2d density]
     293[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/rho2dv1e7_fix_reflec_tau1e5.gif 2d density and velocity]
     294
    290295- Damping preserves the morphology better and helps the star to remain stable. This is consistent with results from the last blog post with different boundary conditions.
    291296
    292 - Fixing the profile at the boundary actually improves stability slightly compared to fixing the profile outside a sphere. (Last plot.)
     297- Fixing the profile at the boundary actually improves stability slightly compared to fixing the profile outside a sphere.
     298
     299- Reflecting BCs (e) gives almost identical results to holding profile fixed on boundaries (b). But with reflecting BCs the simulation is about 30% faster.
    293300
    294301__Conclusions__:\\
    295 - The most successful model for keeping the star stable is III(b) above. Thus III(b) will now be treated as fiducial.
    296 
    297 - From past experiments, we know that stability should improve with increased resolution and larger box size. This should allow larger values of $\tau$ to be imployed, as the current value of $1\times10^5$ is only about $0.2$ dynamical times, smaller than what is used by Ohlmann.
     302- The most successful model for keeping the star stable is III(e) above with constant ambient pressure and density.
    298303
    299304'''IV) Large box (double box size and number of cells to $512^3$, so same physical resolution same)'''\\
    … …  
    312317[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp013/rho1d_Damp013.gif 1d density]
    313318[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp013/P1d_Damp013.gif 1d pressure]\\
    314 DESCRIPTION:
     319DESCRIPTION: Develops slightly boxy morphology.
     320
     321'''b) Reflecting hydro BCs, Multipole expansion Poisson BCs, Velocity damping with $\tau=1\times10^5$s'''\\
     322(i) Constant ambient pressure and density (Damp046)\\
     323[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp046/rho2d_Damp046.gif 2d density]
     324[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp046/rho2dv1e7_Damp046.gif 2d density and velocity]
     325[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp046/P2d_Damp046.gif 2d pressure]
     326[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp046/rho1d_Damp046.gif 1d density]
     327[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp046/P1d_Damp046.gif 1d pressure]\\
     328DESCRIPTION: Develops slightly boxy morphology.
     329
     330'''Comparison with (a) on left and (b) on right'''\\
     331(i) Constant ambient pressure and density\\
     332[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/rho2d_largebox_fix_reflec.gif 2d density]
     333[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/rho2dv1e7_largebox_fix_reflec.gif 2d density and velocity]
     334- The reflecting BCs case is slightly more stable compared to the extrapolated boundaries case.
    315335
    316336'''V) AMR with large box'''\\
    … …  
    322342__Results__:\\
    323343
    324 '''a) Reflecting hydro BCs, Multipole expansion Poisson BCs, Velocity damping with $\tau=1\times10^5$s, $64^3$, maxlevel=4'''\\
     344'''a) Extrapolating hydro BCs, Multipole expansion Poisson BCs, Velocity damping with $\tau=1\times10^5$s, $64^3$, maxlevel=4'''\\
     345(i) Constant ambient pressure and density (Damp047, 27 hrs on comet compute, 576 cores) --arrows scaled as in section II without damping\\
     346[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp047/rho2d_Damp047.gif 2d density]
     347[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp047/rho2dv1e6_Damp047.gif 2d density and velocity]\\
     348DESCRIPTION: More square-shaped and a few times larger velocities than in Sect IV above.
     349
     350'''b) Reflecting hydro BCs, Multipole expansion Poisson BCs, Velocity damping with $\tau=1\times10^5$s, $64^3$, maxlevel=4'''\\
    325351(i) Constant ambient pressure and density (Damp044) --arrows scaled as in section II without damping\\
    326352[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp044/rho2d_Damp044.gif 2d density]
    327353[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Damp044/rho2dv1e6_Damp044.gif 2d density and velocity]\\
    328 DESCRIPTION:
    329 
    330 '''b) Reflecting hydro BCs, Multipole expansion Poisson BCs, No velocity damping, $64^3$, maxlevel=4'''\\
     354DESCRIPTION: More square-shaped and a few times larger velocities than in Sect IV above.
     355
     356'''c) Reflecting hydro BCs, Multipole expansion Poisson BCs, No velocity damping, $64^3$, maxlevel=4'''\\
    331357(ii) Isothermal hydrostatic atmosphere (Atm013)\\
    332358[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Atm013/rho2d_Atm013.gif 2d density]
    333 [http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Atm013/rho2dv1e6_Atm013.gif 2d density and velocity]\\
    334 DESCRIPTION:
     359[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Atm013/rho2d_extended_Atm013.gif 2d density (extended color bar)]
     360[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Atm013/rho2dv1e6_extended_Atm013.gif 2d density (extended color bar) and velocity]\\
     361DESCRIPTION: flow becomes complex, unstable. Code crashed after ~1 dynamical time.
     362
     363'''Comparison with (a) on left and (b) on right'''\\
     364(i) Constant ambient pressure and density\\
     365[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/rho2d_amr_fix_reflec.gif 2d density]
     366[http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/rho2dv1e7_amr_fix_reflec.gif 2d density and velocity]