Dear fellow YTusers, I would like to analyse turbulence in ENZO by comparing velocity difference at different scales. To do this I would like to calculate the velocity difference between each cell and cells a set distance bracket away, square, sum over all cells, and square root to get a turbulent velocity at that length scale. I would the like to do that for many different length scales to form a graph of turbulent velocity against length scale. Has anyone ever done anything like this with YT or have a suggestion for the easiest way to go about doing this? (with either SH = 1 or 0) Many thanks, Libby  Elizabeth HarperClark MA MSci PhD Candidate, Astrophysics, UofT www.astro.utoronto.ca/~hclark hclark@cita.utoronto.ca AIM: edphc1 MSN: edphc1@hotmail.com Skype: eharperclark Office phone: 4169785759
Hi Libby, Work like this has already done with Enzo, in the realm of supersonic turbulence [1]. I wrote the code to calculate the structure functions, and later modified to calculate them in an isolated region. YT wasn't around then, so all of it is in a separate code base, derived from the Enzo source. If you're interested, I'm happy to share it, but I'll need to check with Alexei Kritsuk (the lead researcher), first. Let me know. Rick [1] http://arxiv.org/abs/0704.3851 On Jan 14, 2010, at 2:48 PM, Elizabeth HarperClark wrote:
Dear fellow YTusers,
I would like to analyse turbulence in ENZO by comparing velocity difference at different scales. To do this I would like to calculate the velocity difference between each cell and cells a set distance bracket away, square, sum over all cells, and square root to get a turbulent velocity at that length scale. I would the like to do that for many different length scales to form a graph of turbulent velocity against length scale.
Has anyone ever done anything like this with YT or have a suggestion for the easiest way to go about doing this? (with either SH = 1 or 0)
Many thanks,
Libby
 Elizabeth HarperClark MA MSci PhD Candidate, Astrophysics, UofT
www.astro.utoronto.ca/~hclark hclark@cita.utoronto.ca AIM: edphc1 MSN: edphc1@hotmail.com Skype: eharperclark Office phone: 4169785759 _______________________________________________ ytusers mailing list ytusers@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/ytusersspacepope.org
Libby,
I would like to analyse turbulence in ENZO by comparing velocity difference at different scales. To do this I would like to calculate the velocity difference between each cell and cells a set distance bracket away, square, sum over all cells, and square root to get a turbulent velocity at that length scale. I would the like to do that for many different length scales to form a graph of turbulent velocity against length scale.
This actually shouldn't be too difficult using a kdtree... I'll explain more in a bit, I'm going to take a quick whack at sketching something up... _______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________
participants (3)

Elizabeth HarperClark

Rick Wagner

Stephen Skory