[Nek5000-users] how to get vorticity in the post processing

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

On Fri, 6 Jun 2014, nek5000-users at lists.mcs.anl.gov wrote:

> Hi Neks
> Could any one tell me how to get vorticity in the NEK5000 for post
> processing? I also want to know if it is in the element level or global
> level. For my understanding, I suppose NEK5000 do things in C0 space, how
> could one enforce the continuity in first order derivative?
>
> Thanks
>
> Yours Sincerely
> ------------------------
> Wei Zhang
> Ph.D

Hi Wei,

I would do the following from userchk:

       parameter (lt=lx1*ly1*lz1*lelt)
       common /myvort/ v1(lt),v2(lt),v3(lt)

       if (mod(istep,iostep).eq.0) then
          call comp_vort3(v1,v2,v3,vx,vy,vz)
          call outpost(v1,v2,v3,pr,t,'vrt')
       endif

The result will be put into a file vrtsample0.f00001, etc.,
if your session name is "sample"...   You can then
visualize this field in VisIt.

If you look at the source for comp_vort3 in navier5.f you
will see that the returned field is averaged at the 
interfaces in order to make it continuous.

Paul