Far-field Boundary Conditions
 

How should I set the backflow turbulence parameters for a pressure outlet boundary conditions at distant far-field? Since this is far-field I really don't care about the backflow turbulence so I set the "Backflow Turbulent Intensity" to zero and leave the hydraulic diameter at the default 0.1m. In the steady the far-field boundary is of no importance to the process I am studying, however my simulation log constantly give reverse-flow warnings. Is there a better way to tread this kind of boundary?