1) axial velocity field:


2) axial velocity at inlet plane:


3) RMSE z-velocity at the inlet plane:



"Do not use spectral synthesizer." - Why?

As you can see from my post I also tried no perturbation option. What I didn't show is that I also repeated calculation for Vortex Method. All the 3 tries gave me the same result i.e., Ti at inlet ~3% of mean velocity apart from specified value 0.1%.

What I found in FLUENT manual is: "The turbulence intensity value specified at a velocity inlet for LES, as described in Section 12.20.4, is used to randomly perturb the instantaneous velocity field at the inlet. It does not specify a modeled turbulence quantity."

So, my questions are: why Ti is modelled at the inlet instead of taken explicitly? How explicitly specify Ti at the inlet in LES similarly as in case of RANS?