SIGHT
Supersonic Isothermal self-Gravitating Hydrodynamic Turbulence

Alexei Kritsuk, Michael Norman & Paolo Padoan

I. Driven turbulence in a periodic box: simulations on uniform grids
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Method: PPMDE; Resolution: 64^3, 128^3, 256^3, 512^3, 1024^3; &gamma = 1.001; Mach = 6; Units: L = 1, M = 1, c = 1; Forcing: solenoidal field, k=1-2, fixed pattern;
Density cube (log, 512^3) MPEG: 1.3M
Density thick slice (log, 512^3) MPEG: 2M
Density thick slice (log, 512^3, 100 zones deep) MPEG: 4.5M
AVI: 2.2M
Density slice (log, 512^3, time labeled in dynamical time units, 0 < t < 2.4) MPEG: 1.2M
GIF: 5M
Density slices: structurally "rich", "intermediate", and "poor" (log, 1024^3, t=0.5) JPEG
JPEG
JPEG
Thin and thick slices of div(v) and curl(v) (1024^3, t=0.5) log curl
arcsinh curl
div
arcsinh div
arcsinh div
div movie static 26MB
div movie evolution 31MB
Volumetric rendering of curl(v) (1024^3, t=0.8) arcsinh curl
fig 1 fig 2
fig 3 fig 4
Density PDF (512^3, time labeled in dynamical time units, 0 < t < 2.4) MPEG: 1.6M
Density PDF (256^3 - 1024^3, t = 0.5) PS
Density power spectrum (512^3, time labeled in dynamical time units, 0 < t < 2.4) MPEG: 1.5M
Density power spectrum (256^3 - 1024^3, t = 0.5) PS
Velocity power spectrum (256^3 - 1024^3, t = 0.5) PS
Density slice. Compares methods with different diffusivities: PPM core, PPM with flattening from CW84 A.7-A.10, PPM with flattening and diffusion CW84 A.3 (K=0.1), PPM with flattening and diffusion (K=0.2), ZEUS with C1 =0 C2 = 2, ZEUS with C1 =1 C2 = 1, and Godunov; (256^3; 0 < t < 0.3 in code units; new initial conditions) MPEG: 5.7M
PPM versus ZEUS (Density slices from PPM 256^3, 512^3, and ZEUS 1024^3 simulations at t=0.5)
Density max/min PS
Density, rms PS
Kinetic energy PS
Mach number (rms, mass weighted) PS
Mach number (rms, volume weighted) PS
Velocity, rms PS

II. Driven turbulence in a periodic box: AMR simulations
Method: PPMDE; Base grid: 256^3; AMR: 1 level by 4 is allowed starting from t=0.4, refinement on shocks and shear; Effective resolution: 1024^3; Number of active zones: ~0.74 10^9; &gamma = 1.001; Mach = 6; Units: L = 1, M = 1, c = 1; Dynamical time: t_dyn = 0.083; Forcing: solenoidal field, k=1-2, fixed pattern;
Projected Gas Density (log, effective resolution 1024^2, t=0.439) X-projection
Y-projection
Z-projection
Projected Gas Density (log, effective resolution 1024^2, t=0.501) X-projection
Y-projection
Z-projection
Gas Density Evolution Movies
(log density; X-projection; full box, "thick" slice - 100 zones accross, "thin" slice - 1 zone; t=0.400->0.490)
1024 box
1024 thick
1024 thin
640 box
640 thick
640 thin
Density Cube Movie: Rotation & Close-up (log density; t=0.5) MPEG: 25M
Density Cube Movie: Rotation, Close-up, & Strip-off (log density; t=0.5) MPEG: 32M
Projected density power spectrum (t=0.439) PS
Density PDF (t=0.5) PS MPEG
Density power spectrum (t=0.5) PS MPEG
Velocity power spectrum (t=0.5) PS MPEG
A thin slice through the density cube with boundaries for the first level subgrids (t=0.5) JPEG/EPS
A projection through the density cube (t=0.5) JPEG
Thick slices through the density cube (t=0.5, 150 zones deep) JPEG JPEG JPEG
CASS Journal Club talk (revisited) PDF
AAS205 Poster in PostScript format Letter
Poster
Preprint astro-ph/0411626
Talk at CMSO Workshop, June 2005, Madison, WI PDF

III. Decaying self-gravitating turbulence with AMR
Method: PPMDE; Base grid: 512^3; AMR: 5 levels by 4, refinement based on Truelove et al. (1997) condition; Effective resolution: 2 a.u.; Dynamic range: 5 10^5; &gamma = 1.001; Mach = 6; Units: L = 5pc, time = 27 Myr, m = 3,460 M_sol, c = 184 m/s, density 500 cm-3; Forcing: NONE;
Projected Gas Density (log, based on data with effective resolution 2048^3, RUN2: t=0.426) X-projection
Y-projection
Z-projection
Projected Gas Density: zoom-in on dense filaments (log, based on data with effective resolution 8192^3, RUN2: t=0.426) Z-zoomin
Z-zoom-smooth
Z-zoom-with-grids
Peakfinder results based on RUN2: number of density peaks as a function of... time
separation
max density
Projected Gas Density (log, based on data with effective resolution 2048^3, RUN1: t=0.42466) X-projection
Y-projection
Z-projection
A gallery of images for cores from RUN1 at t=0.4213 HTML/PS/EPS
Core morphology as a function of density (RUN1 t=0.4228) HTML
Hierarchical merging of protostellar disks: a movie from RUN1 MPEG
Cores #10, #11 from RUN1; a hierarchy of Z-projections at t=0.4228 PS/EPS
Paolo's Volterra workshop talk PDF
Poster presented at Protostars and Planets V, Oct. 2005, Waikoloa Village, The Big Island, HI Letter
Poster

This material is based upon work supported by the National Science Foundation under Grants No. 0507768 and 0607675.
Disclaimer: Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.
Number of external visits since Sep 24 2004
akritsuk@ucsd.edu
Last modified: Mon Aug 3 12:10:39 PST 2009
Center for Astrophysics and Space Sciences Laboratory for Computational Astrophysics