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Binary wind capture and accretion diks formation
This page is continuation of http://www.pas.rochester.edu/~martinhe/2011/binary/binary.html.
Sep 27
Find movie of the disk density at http://www.pas.rochester.edu/~martinhe/2011/binary/27sep.gif. Top - logarithmic density maps of the orbital plane. Bottom - 3-D logarithmic density iso-contours viewed edge-on (left); y (vetical) - z (horizontal) plane -perpendicular to the orbital plane- showing linear maps of the Vz velocity component (right). The bottom right panel maintains its blue-red colors close to the left and right boundaries, hence no inflow.
The disk tilts (see bottom left panel). And the tilt angle sem to increase in time. Could this be torques from the AGB wind on the disk?
Angles plot: http://www.pas.rochester.edu/~martinhe/2011/binary/27sep-angles.png
Sep 23
Case with VAGB=5km/s. This is slightly less than the scape velocity from the secondary which, thus, dominates the wind dynamics after a few orbital periods after its gravity is switched on.
Sep 22
a=25AU, VAGB=10km/s (twice as fast as in old sims), lgrid=200AU (twice as long as the old sims), outflow_only BC. I do not see inflow from the boundaries. I see a varying tilt angle (10o-45o) between the disk and the orbital angular momentum vectors. http://www.pas.rochester.edu/~martinhe/2011/binary/22sep.png
Angular momentum projection angles plot is coming soon.
Sep 14
Some corrections to the bear2fix angular momentum projection routines. The still plots in the two links below have been updated accordingly. Mild changes. I've resumed the simulation that corresponds to the links below (a=25 AU, vAGB=5km/s), it's running in bluehive and should go three times further.
Sep 13
Plot of the mean angular momentum direction as a function of radius and time: http://www.pas.rochester.edu/~martinhe/2011/binary/plot.pdf
Plot of the mean angular momentum direction as a function of time: http://www.pas.rochester.edu/~martinhe/2011/binary/13sep.html
Aug
a=25AU, Vagb=5km/s, "sandwich grid" (-5:5,-5:5,-2.5:2.5) AU. This simulation has two phases. During the 1st one, the binaries orbit each other twice, the AGB primary has its slow wind and the secondary only affects the orbit of the primary, but not the gas. This allows the grid to be filled with the AGB wind condition before the disk formation begins. The 2nd simulation phase begins next, when I turn on the gravity between the secondary and the gas. The system orbits 4 times.
2D pole-one logarithmic density map:
http://www.pas.rochester.edu/~martinhe/2011/binary/25-5-fullAGB-2Ddens.gif
3D, 2 panels: pole-on and edge-on views. The disk that forms is not significantly tilted.
http://www.pas.rochester.edu/~martinhe/2011/binary/25-5-fullAGB-2panels-3Ddens.gif
Also ran the same simulation but in a cubic grid. I see significant differences in the disks:
http://www.pas.rochester.edu/~martinhe/2011/binary/25-5-2panels-3Ddens-sandwichVScubicGRIDS.gif
Here's a good still shot too:
http://www.pas.rochester.edu/~martinhe/2011/binary/2panels-3Ddens-sandwichVScubicGRIDS-0180.png
A cubic grid version also with an AGB wind which has filled the grid and a=25AU, but with Vagb=30km/s, is running now. Should have the movie in a few days (before my trip).
Next simulation: a=25AU, Vagb=5km/s. The initial conditions for the disk should be an AGB wind which has expanded beyond the grid boundaries.
The simulation of a=25AU and Vagb=5km/s has run up to 5.7 orbits. Here's a number density [cm-3] logarithmic grayscale map, and an opaque dark-blue map of the grid:
http://www.pas.rochester.edu/~martinhe/2011/binary/25-5-2Ddens.gif (A)
The grid in this simulation is [-5:5,-5:5,-2.5:2.5], "a sandwich", and each computational length unit=10AU. This makes the simulation faster without compromising disk formation dynamics. I see complex flow patterns. The rotation of the diks is synchronous with the orbital one.
Here a 3D view of the number density of this simulation:
http://www.pas.rochester.edu/~martinhe/2011/binary/25-5-2panels-3Ddens.gif (B)
The left panel is a perspective view. The AGB primary is the red particle. The orbital plane is opaque, in the middle of the figures. This is a viewing angle of about 10 degrees. Disk material below the orbital plane is shaded. The right panel shows the same simulations but normal to the orbital plane and from bottom to top relative to the left panel.
Newest runs (as fas as they've gotten). a=binary separation [AU] , v=AGB [km/s] wind velocity.
a=5, v=5. http://www.pas.rochester.edu/~martinhe/2011/binary/summer/18jul-densISOCONTOURS-a.gif
a=5, v=30. http://www.pas.rochester.edu/~martinhe/2011/binary/summer/18jul-densISOCONTOURS-b.gif
a=25, v=5. Tired to run with lScale=10AU and the same grid size as the tow simulations above (just at the post of 13 june, http://www.pas.rochester.edu/~martinhe/2011/binary/binary.html). This setup, however, produced wrongly high v, because the code's velocity scale only depends on tempScale (i.e. velscale \propto tempscale and not to lscale). Easy solution would be to reduce tempscale and rerun. Yet, I decided to change as little parameters as possible between different runs (a=5 and a=25), so I'm now running this case (a=25 v=5) with lscale =1AU and a 4 times larger grid than in the a=5 case. Progress, about .5 orbit.
a=25, v=30. Very problematic run. Need to adjust AR to follow the wind while it travels between the stars. Currently running in bluehive with the above described setup. Progress, I only have 3 chombos, ~ ¼ of the 1st orbit.
Difficult to get much further before the Tenerife conference.
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