Changes between Version 44 and Version 45 of u/erica/CoreCollapseBlog

Timestamp:

04/17/18 12:40:02 (7 years ago)

Author:

Erica Kaminski

Comment:

—

u/erica/CoreCollapseBlog

@@ -1 +1 @@
 == 4/15/18 ==
 
-Fixed the AMR criteria so that just the inner regions of the sphere are refined and moved to modeling the collapse in 3D, beginning with just an octant. Running the code for a freefall time using the density of the inner region (~100 milliseconds) required extremely small initial time steps to avoid high cfls and nans. Kept increasing the initial max speed to get around this. Once the simulation got past a few frames, noticed strange behavior along the boundary, which looked like a pile up of mass there. The boundary conditions are currently set to outflow only on the faces of the cube, and the Poisson BC's to multipole... 
+Fixed the AMR criteria so that just the inner regions of the sphere are refined and moved to modeling the collapse in 3D, simulating an octant of the domain (running the full cube or an octant didn't make a noticeable difference in the behavior of the boundaries). 
 
-Looking at Phi along the faces of the boundary at the first frame showed unexpected behavior -- spheres of hi Phi centered on the outer faces of the cube, but no longer on the high density core. Switching to periodic BCs on Phi seemed to fix the issue, although multipole BCs over periodic BCs for the Poisson solver in this setup seem preferable. Will need to track down where this is a bug in the multipole BCs.
+Running the code for a freefall time using the density of the inner region (~100 milliseconds):
 
-Running a cube or an octant doesn't seem to make a difference in the behavior of the boundaries, testing both periodic and multipole Poisson BCs..
+$t_{ff}\approx .5 \frac{1}{\sqrt{G \rho}}$
 
+|| $T_{sim}$ || $.6 (CU) \approx 2 ~tff$ || 
+|| Hydro BC's ||Outflow only (stepping on outer density and temp) on outward facing sides, reflecting on inside faces||
+|| Poisson BC's || Multipole on outward facing sides, reflecting on inner ||
+|| Self-gravity || On ||
 
+==== Testing HSE ==== 
 
-Was noticing strange behavior along the boundary, which looked like a pile up of material there.  
+As shown below, the profiles generated by AstroBEAR's HSE module closely match the input progenitor profiles, which are in HSE. Interpolation onto the grid for the hydro simulation can be closer or further from these initial profiles depending on resolution as the following line plot shows:
+
+[[Image()]]
+
+At a resolution of ~, the sphere is very close to HSE within .1 of its radius.
 
 == 3/15/ 18 ==