Update 09/21/2015 - Eddie

New 2-D Mach stem runs with lower M

I tested gamma = 1.4 with 4 different separations: 4.5, 5, 6, 6.5 rclump. I chose these separations because they are right on the edges of the different regimes (see figure below).

Velocity was lowered from 50 km/s to 15 km/s resulting in Mach number being decreased from 5.18 to 1.55. I had to lower the maximum of the density scale from 35 to 16 since these are weaker shocks (number density in computational units of 10,000 cm-3).

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The table below summarizes the Mach stem behavior for the relevant models after 75 years. To characterize this time in terms of clump-crossing times, it would be about 40 for the original M = 5.18 runs and about 12 for the new M = 1.55 runs. (TMS = Transient Mach Stem, SB = Single Bow, SMS = Stable Mach Stem, RR = Regular Reflection)

d (rclump) M = 5.18 result M = 1.55 result
4.5 TMS, SB TMS, SB
5 SMS TMS, SB
6 SMS TMS, SB
6.5 RR TMS, SB

As you can see, with a lower M, we now get a single bow in every model. I think this is because there is less pre-shock ram pressure to keep the enhanced post-shock thermal pressure at bay. In regards to Mach stems, I see two possibilities: 1) Achieving a SMS is impossible, and the behavior will transition to RR at larger separations, or 2) the SMS region has just shifted to larger separations. Either way, I want to do some more runs to see if I can find the SMS regime for this lower M.


Other Stuff

  • Debugging the error in the projections. The error I'm getting now is not where I expected it to be which is confusing. It is in data_declarations.f90 where the Info object is initialized. Maybe I need to run with more cores to get by this part of the code, and trigger the real error?
  • Still haven't received any confirmation about my guest account on the Rice machines.
  • I'm in the process of moving some data off of BlueHive to make room for some 3D pulsed jet runs.
  • PAPER EDITS!!! There is a lot to be done, so I'm mainly busy with this now.

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