[FLASH-USERS] StirTurb Restart

[Evan Scannapieco]

Hi Chris,

We also modified Stir_turb to do purely solenoidal driving, as well as to drive scalars continuously or instantaneously at the same time, change the correlation in time, etc… and this is what we used in our papers.  But we never messed with the restart problem.  

I believe with FLASH3 you could sometimes get a restart with incomplete information that didn't crash, but wasn't quite right either, Liubin would know better than I would. In FLASH 4 even this doesn't seem possible right however, although perhaps it is with the parallel IO as Klaus says.   I'm in the midst of testing a serial solution to getting IO_readUserArray to work, but if you've got one I guess I could try that one too if you don't mind.

Best,

Evan

On Sep 9, 2013, at 3:27 PM, Christoph Federrath <christoph.federrath at monash.edu> wrote:

> 
> Hi Evan, Hi Klaus,
> 
> I'm not sure what exactly the problem is, but I figured that all out long time ago when I switched to FLASH3 and now FLASH4, as I've been running turbulent stirring for years now in FLASH. First, I have to say that the existing "stirturb" module does not produce a purely solenoidal driving field contrary to what the manual says; there is a bug in how the projection in Fourier space is done. I also had to modify the IO routines if I remember correctly to get the restarting fixed. Basically, the modes and other variables were not written to the checkpoint file, and so the simulation did not continue correctly on restart (meaning it probably did restart, but gave results that depended on whether a restart was done or not). I have fixed this, but I went further and modified the stirring module to now read in a predefined forcing sequence, which we used in a code comparison.
> 
> My plan was to make the modified turbulence driving module available anyway at some point. If anybody is interested, I can send it to you; works well on restart; supports purely solenoidal or compressive driving and any combination; and allows to define stirring with a predefined sequence (you can always reconstruct the driving sequence afterwards, extend it, etc).
> 
> Kind regards,
> 
> Christoph
> 
> ________________________________
> Dr. Christoph Federrath
> School of Mathematical Sciences,
> Monash University,
> Clayton, Vic 3800, Australia
> +61 3 9905 9760
> http://www.ita.uni-heidelberg.de/~chfeder/index.shtml?lang=en
>