[lucasbraganca]

Hi.
I'm running a standard k-omega turbulent model on a channel flow with a smooth change of cross section. My preliminary fluent result seems very strange a few meters after the inlet. There is a sudden flattening of the velocity profile that makes no physical sense and that I can´t get rid of. I've changed the setups a thousand times(e.g. discretization schemes and so forth) but nothing seems to change this scenario.

Alongside fluent, I've also done the very same simulation on OpenFOAM and CFX and both agree with each other pretty well.

What might be causing this weird behavior?

I'm attaching a simple qualitative contour plot just to show where fluent is erring.

Some infos about my geometry and boundary conditions:

-> Channel flow with change of cross section.
-> 2D, steady and turbulent (Re=12600)
-> Inlet velocity profile comes from another simulation (I´m using a profile data file to define the inlet boundary condition on fluent)
-> Fine mesh at walls (y+ ~ 1)


More specifications can be found on the following website:
https://turbmodels.larc.nasa.gov/Oth...nnel12600.html