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Update 11/29
- MHD begins to throw pressure protections between 1e-5 and 1e-2. They are thrown, as far as I can tell, immediately upon creation of the planet (went down to final time of 1e-100, with 100 frames). Up to this point, the fields and contours all look identical to the zero-field case, but want to check out early times for small B:
(Attempting to narrow down where protections start to happen I did a stupid - running three jobs again.)
10 frames of output posted on alfalfa for B=1e-2, to 0.01 orbits: MHD data
- Ran a larger WASP-12 simulation, but it also crashed - what exactly does changing the start time do computationally-speaking (for data output purposes)? It also runs until the planet is created - connection? But up to that point, stellar wind evolution is uninteresting/unchanged.
Meeting Update --11/29/16
- 2D Wire Turbulence
- Wind cannot pass the wire: 2D mhd movie
- Metal Cooling
- Eddie's looking for the cooling table&code for Aluminum+Argon.
- 3D Wire Turbulence with Analytic Cooling
- Analytic Cooling Parameters and Cooling Length
- hydro results
| no Cooling |  | movie |
| Cooling Length 1 a |  | movie |
| Cooling Length 0.5 a | movie |
Update 11/15
- Removed extra refinement from MHD simulations and extended boundaries by 0.025 in each direction. Still have subsonic material leaving grid in x-y plane, as well as both subsonic and sub-alfvenic eventually leaving in the z direction. Also, alfven speed is becoming very large in a concentrated area around frame 24 and increasing computation time significantly - not sure if there's anything to do about this.
Definitely going to increase grid size more. Anything else to do about computation time and irregularity of contours?
- WASP-12b simulations appear to have gone extremely well, on the other hand. Ran a test with new parameters for density, bow shock radius, etc.:
| 0.036180 | ratio of planet radius to orbital separation | |
| 0.324198 | ratio of stellar radius to orbital separation | |
| 0.069149 | ratio of Hill radius to orbital separation (from planet) | |
| 0.125384 | ratio of bow shock radius to orbital separation (from planet) | |
| 0.314214 | ratio of planet sonic radius to orbital separation (from planet) | |
| 0.314214 | ratio of coriolis radius to orbital separation (from planet) | |
| 87.507134 | ratio of densities at bow shock | |
| 19.542018 | stellar lambda | |
| 17.369379 | planetary lambda | |
| Orbital separation | 0.022930 | AU |
| Mass of Star | 1.349999 | solar masses |
| Mass of Planet | 1.405393 | Jupiter masses |
| Radius of Star | 1.599000 | solar radii |
| Radius of Planet | 1.736000 | Jupiter radii |
| Temperature of Star | 999999.016096 | Kelvin |
| Temperature of Planet | 10009.919196 | Kelvin |
| Density of Star | 3.211200e-17 | g/cc |
| Density of Planet | 3.211200e-15 | g/cc |
| Orbital period | 1.090679 | days |
| Mass loss from Star | 1.002167e-18 | solar masses per yr |
| Mass loss from Planet | 5.460294e+07 | g/s |
| Mach number of Stellar wind at shock | 2.050641e-01 | |
| Mach number of Planetary wind at shock | 4.368280e-01 | |
| predicted bow shock radius in units of lscale | 1.255086e-01 |
Mass loss rates may be a bit low - can increase both densities to get higher, but sims look good:
Still a slight spiral feature in the initial stellar wind, before planet is created, but doesn't seem to persist (may just be Coriolis effects - doesn't appear to originate from stellar surface). Ran 9 full orbits - reaches quasi-steady state after about 3 days:
meeting update
Did some modeling of random particle distributions to understand galactic colonization in a static system.
Here is a plot showing the number of 'isolated' subgroups of systems given a probe range. The number of isolated subgroups (y-axis) is scaled by N and the probe range (x-axis) is scaled by (1/ND) where D is the dimension. This demonstrates the cutoff in propagation for static systems when the density drops to only a few habitable systems within range on average. The two sets of red lines are for 2D and 3D and they were calculated with 1000 and 10,000 systems. (The 2D system has the longer tail)
And here is another plot showing the fraction of the number of systems that can be reached starting at a point chosen at random as a function of the average number of systems within a sphere of radius probe range.
Nov. 2nd, 2016 Meeting Update
Need letter to YCAA today
Questions on Hubble Proposal Draft
Paper list on zoom-in: http://adsabs.harvard.edu/cgi-bin/nph-abs_connect?library&libname=Zoom-in&libid=56b0f4173b
Have an interview next week at Univ. of Hertfordshire. This is with: Jim Dale, Martin Krause, Martin Hardcastle (as Director of the Centre), and Janet Drew (panel chair, and PI of the grant)
Dr Strange this weekend?
Wire Turbulence
- 3D result with bar grid
- hydro: no turbulence along z direction movie
- mhd: find turbulence along z direction version 1 code movie; version 2 code movie;
- deviation of velocity
|
*2D with bar grid
- memory allocation error for mhd on Bluestreak. Runs OK on Bluehive
- 2D hydro movie; 2D mhd movie
Update 11/2
- Finished GRFP application on Friday. Waiting on two letters of recommendation (as of noon today).
- WASP-12b: According to matlab script, no bow shock. Plot for ram pressures is
Initialized stellar wind out too far, so that planet was created inside:
- MHD simulations of HD209458b: attempting to control refinement. On most recent attempt, segfaulted:
Relevant code snippet:
SUBROUTINE ProblemSetErrFlag(pos, Info)
TYPE(InfoDef) :: Info
REAL(KIND=qPREC), DIMENSION(:), INTENT(IN) :: pos
REAL(KIND=qPREC) :: x(3), r
x=pos-PlanetPos
r=sqrt(sum(x**2))
! Force lowest resolution outside of 5*Rp
IF (r > 5*planetRadius) THEN
Info%ErrFlag = 0
END IF
END SUBROUTINE ProblemSetErrFlag
Next thought is to write a separate subroutine that can be called in ProblemSetErrFlag, similar to the subroutines being called in the before step - but is this too simplistic?
- Also time to register for next semester - high-energy astrophysics or compressible fluids?
- Finally, 2D Owen and Adams MHD simulations.
Binary star
Test an isolated AGB star burst. Below is a plot of its mass loss rate (solid line) measured at 10 AU radii and the initial burst velocity (dash line).
Staff et al. (2016) calculated the 3-D mass loss rate (ejection) in common envelop evolution.
