[Nek5000-users] Channel Flow 1D/2D energy spectra

[nek5000-users at lists.mcs.anl.gov]

Hi Philipp,

Thanks for the reply. So you are saying that I would map the output to a
simpler mesh then do the fourier transforms for the spectras?  Would you be
able to give me a basic idea behind how the spectra could be computed using
a simpler mesh?

Thanks,
William

On 20 August 2018 at 02:42, <nek5000-users at lists.mcs.anl.gov> wrote:

> Hi,
> For most cases, we typically do all these things (statistics, spectra,
> budgets) outside of Nek5000, on simpler meshes (equidistant or polar meshes
> for instance). For instance in our paper on pipe flow, we show exactly
> those 1D and 2D energy spectra.
>
> https://link.springer.com/article/10.1007/s10494-013-9482-8
>
> For your purpose however, I would suggest some physical space filter with
> specific transfer function. That might be the easiest way.
>
> Best regards,
> Philipp
>
>
> On 2018-08-19 07:54, nek5000-users at lists.mcs.anl.gov wrote:
>
>> Hi Nek Users,
>>
>> I am a new user to Nek5000 and I have been playing around with the
>> channel flow example. I have set up an example similar to Kim and Moin. The
>> mean velocity profile seems to agree quite well so I have set up the
>> initial case correctly.  Now, my goal is to try and recreate the energy
>> spectra as in the paper above. I am confused as to the best way to go about
>> this, would it be best to obtain output files then do the post processing
>> outside of Nek or can it be done inside Nek as well?
>>
>> My ultimate goal is to be able to cut off some of the higher energy modes
>> and transform it back and feed it at the start of the simulation. Any
>> advice on this would be appreciated as I have been struggling as to how I
>> should proceed in Nek5000.
>>
>> Thanks in advance,
>> David
>>
>>
>> _______________________________________________
>> Nek5000-users mailing list
>> Nek5000-users at lists.mcs.anl.gov
>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users
>>
>> _______________________________________________
> Nek5000-users mailing list
> Nek5000-users at lists.mcs.anl.gov
> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/nek5000-users/attachments/20180820/5b01b317/attachment.html>