[letzel]

Dear Foamers,

similar to this thread on how to calculate a turbulent heat flux <u'T'>, where <...> denotes a local time average, I plan to calculate the vertical turbulent momentum fluxes <w'u'> and <w'v'>. Plus, the vertical total momentum fluxes <wu> and <wv>. This is in order to monitor OpenFOAM LES of the atmospheric boundary layer.

I want to output these data not for the total domain but only as one-dimensional vertical profiles at say ten or twenty locations within the simulation domain, e.g. for postprocessing with XmGrace.

My question is which is the best way to efficiently calculate and output these data.

Since I have a modified solver anyway, it would be possible to code the time averaging according to this post for U as well as the products wu and wv. The time-averages <w'u'> and <w'v'> could be calculated in a similar manner in the solver. But I would expect that this wastes CPU time as well as RAM since the output is actually only needed for ten to twenty one-dimensional vertical profiles.

So, is there a way to calculate these data more efficiently only where output is needed? I have a vague feeling that swak4foam may accomplish this. If so, how?

And is there any elegant way to combine the definition of ten, twenty vertical profiles? If I use ten, twenty different sampledSet, my controlDict would become quite long.

Looking forward to hear your advices,
Marcus