reimplement drag in riemann hydro

star/defaults/controls.defaults

@@ -2985,7 +2985,7 @@
     conv_premix_dump_snapshots = .false.
 
 
-   ! Rayleigh Taylor Instability
+   ! Rayleigh-Taylor Instability
    ! ____________________________
 
       ! derived from Paul Duffell's code RT1D.
@@ -8241,9 +8241,12 @@
       ! ::
 
     use_dPrad_dm_form_of_T_gradient_eqn = .false.
-    use_gradT_actual_vs_gradT_MLT_for_T_gradient_eqn = .false.
-
-
+    use_gradT_actual_vs_gradT_MLT_for_T_gradient_eqn = .false.    
+
+
+      ! Hydrodynamic drag
+      ! =================
+
       ! drag_coefficient
       ! ~~~~~~~~~~~~~~~~
       ! min_q_for_drag
@@ -8274,13 +8277,34 @@
     use_drag_energy = .true.
     drag_coefficient = 0d0
     min_q_for_drag = 0d0
+
+
+      ! v_drag_factor
+      ! ~~~~~~~~~~~~~
+      ! v_drag
+      ! ~~~~~~
+      ! q_for_v_drag_full_off
+      ! ~~~~~~~~~~~~~~~~~~~~~
+      ! q_for_v_drag_full_on
+      ! ~~~~~~~~~~~~~~~~~~~~
 
 
-      ! for hydro comparison tests (e.g., Sedov)
+      ! Implemented only for u_flag right now. Adds a pseudo drag term of the form
+      ! -v_drag_factor*(v-v_drag)^2/r, can be used damp velocities in outer layers
+      ! of a star. Effect is full on for q>q_for_v_drag_full_on and full off for
+      ! q < q_for_v_drag_full_off.
+
+      ! ::
+
+    v_drag_factor = 0d0
+    v_drag = 0d0
+    q_for_v_drag_full_off = 0.95d0
+    q_for_v_drag_full_on = 0.96d0
 
 
       ! Rayleigh-Taylor Instability
       ! ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+      ! for hydro comparison tests (e.g., Sedov)
       ! RTI_A
       ! ~~~~~
       ! RTI_B

star/dev_cases_test_TDC/dev_TDC_through_ppisn/README.rst

@@ -0,0 +1,21 @@
+.. _ppisn:
+
+*****
+ppisn
+*****
+
+This test case evolves a very massive helium star from the He-ZAMS
+up to the ocurrence of a pulsational pair-instability event (see |Marchant2019|).
+
+.. |Marchant2019| replace:: `Marchant et al. 2019 <https://ui.adsabs.harvard.edu/abs/2019ApJ...882...36M/abstract>`__
+
+Initialization of the model
+===========================
+The initial mass of the helium star is set in ``inlist_extra``
+
+.. literalinclude:: ../../../star/test_suite/ppisn/inlist_extra
+
+In this case we use a :math:`72 M_\odot`
+
+Last-Updated: 2019-11-12 (mesa r12413) by Pablo Marchant
+

star/dev_cases_test_TDC/dev_TDC_through_ppisn/README_DEV

@@ -0,0 +1,7 @@
+Test cases with names beginning in "DEV_" are under development.
+This means that they are not ready for consideration by general users as a "how to" guide for research to be published.
+
+Play but don't publish!
+
+The situation is similar to that for options in controls_dev.defaults and star_job_dev.defaults.
+

star/dev_cases_test_TDC/dev_TDC_through_ppisn/ck

@@ -0,0 +1,7 @@
+#!/bin/bash
+
+# this provides the definition of check_one
+# check_one
+source "${MESA_DIR}/star/test_suite/test_suite_helpers"
+
+check_one

star/dev_cases_test_TDC/dev_TDC_through_ppisn/clean

@@ -0,0 +1,4 @@
+#!/bin/bash
+
+cd make
+make clean