Posts for the month of December 2019

Update 12/16

MHD

See my page for movies of moderate-field runs.

Next steps: Fix field lines in left (& right?) boundary. Test starting from complete field. Attempt higher fields (will likely require high resolution at planet boundary - means need to spend some time integrating AMR line transfer).

Charge Exchange

https://www.pas.rochester.edu/~adebrech/ChargeExchange/HD209458b_charge_exchange0000.png

Successfully replaced ambient for low-wind run, but running into pressure protections - trying to work through them now.

Misc

Exoplanets 3 registration is open. AAS dress code?

COMMON ENVELOPE SIMULATIONS

New Work

  • Plan for Paper IV
  • Started analysis for Run 183 (AGB)
  • Backing up files on TACC Ranch (about half full)
  • Force postprocessing for Run 183 completed on bluehive

Results

Plan for Paper IV

  • Title: Effects of varying the primary star evolutionary state in 3D global simulations of common envelope evolution
  • Abstract:
    • First AGB CE simulation with high resolution (“present generation” resolution)
    • Result 1: summarize simulation outcome
    • Compare with RGB simulation to assess the differences and similarities
      • Result 2: orbital evolution comparison
      • Result 3: force comparison
      • Result 4: envelope mass unbinding evolution comparison
      • Result 5: potential for constraining alpha
    • Result 6: lessons learnt about the numerics
  • Figures
    1. RGB and AGB initial profiles (density, internal energy, total energy)
    2. Separation vs time curves comparison, with a(t/Porb0)/a0
    3. Density, orbital plane, 4 snapshots
    4. Normalized energy, orbital plane 4 snapshots at same times as for density
    5. Force on particle 2 (in rest frame of particle 1) vs t/Porb0
    6. Unbound mass vs t/Porb0
    7. Percent energy change —convergence study
    8. Unbinding efficiency epsilon as a function of time (or leave for paper on energy formalism?)

Separation vs time

http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Run183/p_mult_183_143.png

Detail of flow near particles at late times

http://www.pas.rochester.edu/~lchamandy/Graphics/RGB/Post-sink_particle/Post-modified_Lane_Emden/Run183/flow_detail_density_Run183.png

Density and normalized gas energy

Run 183 Density and Normalized gas energy
Run 183 Normalized gas energy definition comparison (a-b)/max(a,b), as in Paper II, on the left, and (a-b)/(a+b) on the right

Next steps

  • Carry out analysis, one figure at a time
  • Keep adding to draft of paper
  • Prepare Xsede proposal (renewal) for Jan 15
  • Compute mean separation abar(t) from orbit data (non-trivial!)
  • Submit by Apr 1

Dust in AstroBEAR - Update 2019/12/09 and 2019/12/16

Objectives

  • Debug & test advection & sputtering routines
  • Continue implementation of grain-grain collisions

Progress:

  • Debugging: Still debugging, found one big bug and fix it last week so going well. Found an issue with the interpolation routines for the dust. Not quite sure yet what's happening here.
  • Grain Growth: I think the ion trapping routine is more or less bug-free now, working on feedback effects on the gas since we couldn't consider that for dust post-processing.
  • Grain-Grain Collisions: I'd say this is about 30% done now, aiming to finish by the new year
  • New Problem Setup: Finished tweaking that. A sample simulation can be found here: Video.

Issues & Questions:

  • Performance: Is there a way to find out how much time the code spends in certain routines?

Update 10/2

MHD

The bug was tracked down last week. The low-field test case now works (known working up to a stellar beta of 10-2), so I'm experimenting with some values of the ramping to get the higher-field cases working.

Charge Exchange

Here's a movie up to frame 30:

https://www.pas.rochester.edu/~adebrech/ChargeExchange/HD209458b_charge_exchange0000.png

https://www.pas.rochester.edu/~adebrech/ChargeExchange/HD209458b_charge_exchange_species0000.png

And here's the latest frame:

https://www.pas.rochester.edu/~adebrech/ChargeExchange/HD209458b_charge_exchange0034.png

I've implemented a check to make sure the stellar wind has a greater total pressure than the ambient, and if not to replace the ambient (or material at a density threshold approximately equal to the ambient density) with the stellar wind (which will be a much more significant shock to the simulation, I think, but probably can't be helped). Still testing this.

Scaling Test

Still fighting with the KNL nodes. I'm talking with Baowei to try to figure out why.

Dust in AstroBEAR - Update 2019/12/02

Objectives

  • Debug & test advection & sputtering routines
  • Continue implementation of grain-grain collisions

Progress:

  • Debugging: Currently cleaning up the routines. Fixed some stuff but still ironing out some issues.
  • Grain-Grain Collisions: Continued the collision routines a bit but as mentioned this will take some time as I want to prioritise sputtering and drag.
  • New Problem Setup: Set up a problem for supernova ejecta interaction with a wind-driven shell.Illustration here. (Data for time-dependent wind can be taken from Schaller et al. 1992 and Vink et al. 2001)

Issues:

  • Dust Processing: Still debugging but going ok.
  • New Problem Setup: Working but is there an easier way?

Planet-Civ Evolution Project Update 12/2