Mathematics – Logic
Scientific paper
Dec 2004
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004aas...20513914k&link_type=abstract
American Astronomical Society Meeting 205, #139.14; Bulletin of the American Astronomical Society, Vol. 36, p.1575
Mathematics
Logic
Scientific paper
We report first results from 3D numerical simulations of homogeneous supersonic hydrodynamic turbulence with the massively parallel adaptive mesh refinement (AMR) code Enzo. The code uses the Piecewise Parabolic Method (PPM, Woodward & Colella 1984) to solve the Euler equations in a box with periodic boundary conditions and effective grid resolution up to 10243. Our model describes driven Mach 6 turbulence and assumes an isothermal equation of state, thus roughly approximating the conditions in molecular clouds. We use one level of mesh refinement by a factor of four on shocks and shear to follow the most important dissipative structures of turbulence with the highest resolution.
Exactly as predicted by a phenomenological intermittency model, as soon as the resolution is high enough to provide integral/dissipative scale separation (this happens at ˜ 5123 zones for Euler turbulence simulations with PPM), the volume filling factor for subgrids scales as Re3D/(1+D)}/Re{9/4, where D=2 is the dimension of the dissipative structures and Re is the Reynolds number. This scaling makes AMR simulations of high-Re flows more efficient than equivalent simulations on uniform grids.
We compared PDFs and 3D power spectra of gas density as well as 3D velocity power spectra from our AMR and unigrid runs and found them in excellent agreement with each other. Based on these results, we discuss the signature of dissipative structures in the statistical properties of supersonic turbulence and their role in overall flow dynamics.
This work was partially supported by NRAC allocation MCA098020S and utilized computing resources provided by the San Diego Supercomputer Center. We would also like to thank Sun Microsystems' RASCAL Lab for the opportunity to evaluate their new high-availability framework for scientific computing.
Kritsuk Alexei G.
Norman Michael L.
Padoan Paolo
No associations
LandOfFree
Supersonic Turbulence: Intermittency, and Simulations with Adaptive Meshes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Supersonic Turbulence: Intermittency, and Simulations with Adaptive Meshes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Supersonic Turbulence: Intermittency, and Simulations with Adaptive Meshes will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1643510