Meeting Update 01/09/2014 - Eddie

Mach Stems

Ran the d = 20 simulation with an extended lower y boundary. The size of the y-domain was doubled from 40 to 80. The distance from the clump center to the bottom boundary was increased from 30 to 70.

movie​

Here is a comparison with the previous run. The run with the extended boundary is on the right, but I am not plotting the extended region.

movie​

So the bottom boundary does appear to be playing a role in regards to this nonphysical upwards motion. Now we just have to decide what to do about it. The easiest thing would be to extend the boundary (perhaps even farther than I already have), and then ignore the bottom portion of the domain. This would be ok for these 2D runs, but the 3D runs might be different. This also might not work for the runs where I put one or both clumps in motion.


3D Pulsed Jet

Jonathan implemented a new CFL and maxspeed check for the astrobear standard output. When there is a "high CFL restart", it now reports the maxspeed across all processors instead of just processor 0, and it gives the position. Here is an example: 

High hydro CFL (  0.21E+01 >   0.80E+00) found at position (  0.1875E+00,   0.8929E-02,   0.9911E+00) on processor   3175, due to a maxspeed of   0.27E+03 - Restarting Step

In regards to my pulsed jet problem, this is great for figuring out where in the domain the maxspeed is getting too high. This is most likely due to low densities and thus high alfven velocities.

However, my simulations are also showing restarts "due to nan in flux". We thought these might be caused by the high CFLs and maxspeeds, but these restarts are not preceded by high CFLs. Attached to this post is a copy of the standard out from my most recent run on kraken.

The issue has probably evolved since we first started this problem, but the original ticket created for the 3D pulsed jet runs is ticket #289. The problem could also be related to tickets #301 and #302. For simplicity, I closed #289 and #302, and started a new ticket #330.

Attachments (5)

Comments

No comments.