[MarijaB]

Dear all,

In order to understand how to specify the Reynolds stresses at the inlet, I compared the Reynolds stresses obtained with OpenFOAM's function UPrime2Mean with diagonal stresses calculated from extracting the variance of the velocity components from the probes time-histories (var() in Matlab).
The results obtained with OpenFOAM and the results what I get by calculating the variance of the velocity from probes are very different, as it can be seen in the figure:



I still cannot figure what am I doing wrong and what is the source of this mismatch. Is it correct to define the Reynolds stresses u'u', v'v', w'w' just like the variance of the velocity components?

[I used OpenFOAM's 1606+ and the case channel395DFSEM. In addition to the original case I just added velocity and pressure monitors.]

Any help is appreciated,
Marija