Turbulent Intensity too large!
 

Fluent's modeling of duct incompressible flow shows turbulent intensity about I=100-400% in regions closed to the walls, in the vortex wake after central body and outlet jet. Turbulence model is k-epsilon. Mesh is rather fine (y+=3). Pressure inlet and outlet conditions are set to I=1% and hydraulics diameter=2m.

Would you help me?

Re: Turbulent Intensity too large!
 

What kind of mesh are you analyzing?

Re: Turbulent Intensity too large!
 

Mesh generating fragments:

'undo begingroup' 'blayer create "bl_virtual_wall_3" first 0.0001 growth 1.2 total 0.0186688 \' 'rows 20 transition 1 trows 0 continuous' 'blayer attach "bl_virtual_wall_3" face "face_throat_1" edge "virtual_wall_3"' 'undo endgroup' ... 'face mesh "face_throat_1" triangle size 1' 'face mesh "face_throat_2" triangle size 1' 'face mesh "face_before_grid" triangle size 1' 'face mesh "face_grid" map size 1' 'face mesh "face_after_grid" map size 1' 'face mesh "face_camera" pave size 1' 'face mesh "face_dif" map size 1' 'face mesh "face_outlet" pave size 1'

Re: Turbulent Intensity too large!
 

Hi,

May I suggest that you have a look into the reference values used in calculating the intensity as that may give you a clearer meaning of what that intensity means in your model.

Re: Turbulent Intensity too large!
 

Friend:

Thanks for the help!