.. _conductive_flame: **************** conductive_flame **************** .. tags:: star, carbon-burning, conductive-flame, deflagration, carbon-oxygen-mixture, flame-speed This test suite case models a conductively-propagated deflagration wave ("flame") in a high-density, degenerate carbon-oxygen mixture. It is similar to a calculation presented by |Timmes1992|. .. warning:: Careful modeling of the flame speed requires a much larger nuclear network than the 21 isotope network used in this test. |Timmes1992| use a 130 isotope network, |Chamulak2007| use a 430 isotope network, and |Schwab2020| use a 495 isotope network. Unlike most MESA calculations, this models a small sphere of material (instead of an entire star). The initial model is built in ``run_star_extras`` using the ``other_build_initial_model`` hook. A spatially uniform model with a given density, temperature, and composition is constructed. A small hot spot is then added at the center of the model. The properties of this initial model can be controlled from the inlist. .. literalinclude:: ../../../star/test_suite/conductive_flame/inlist_conductive_flame :language: fortran :start-after: ! use our own routine to build the model :end-at: x_ctrl(8) The inner boundary is at r = 0. The outer boundary has a fixed temperature and a fixed pressure equal to the initial pressure of the material. This is achieved via the ``use_other_surface_PT`` hook, but can also be done using the ``fixed_Psurf_and_Tsurf`` atmosphere option. After an initial transient, the entire flame structure, approximately isobaric, propagates into the upstream fuel with a unique speed and width. The test succeeds if the flame successfully propagates through half of the domain and reports values for the flame width and speed that are within 10% of the specified reference values (see inlist). The flame width and speed are reported to the TestHub. The flame speed is measured using the time/position when the flame is 30% of the way through the domain and time/position at the end of the test. The flame width is measured at the end of the test as the width over which ``eps_nuc`` is greater than 10% of its peak value. See routine ``flame_properties`` in the ``run_star_extras.f90``. .. image:: ../../../star/test_suite/conductive_flame/docs/grid1000598.png :width: 100% pgstar commands used for the plots above: .. literalinclude:: ../../../star/test_suite/conductive_flame/inlist_pgstar :language: console .. |Timmes1992| replace:: `Timmes & Woosley (1992) `__ .. |Chamulak2007| replace:: `Chamulak et al. (2007) `__ .. |Schwab2020| replace:: `Schwab et al. (2020) `__ Last-Updated: 2021-06-21 (mesa b2364463) by Josiah Schwab, + documentation 2024-01-22 EbF Last-Run: 12Apr2026 (MESA c79eae5c5) by vincentva on procyon in 505 seconds using 8 threads.