I want to ask how to get the turbulence Reynolds normal stress and the Urms in the example of channel3d ,so as to compare with DNS data and prove the applicability of the channel3d.
have a look at the functor SuperLatticeTimeAveragedCrossCorrelationF3D. You can find the corresponding source code and documentation in src/functors/lattice/timeAveraged/superLatticeTimeAveraged3D.h(h)