[Lattouf15]

Hello,

I have to simulate a flow in 2.5m pipe with a diametre of 6mm.

I'm currently using K epsilon turbulence model, but the simulation keeps crashing for different mass flows of air. We're talking here of 2g/s, 1g/s and 0.66 g/s.

The goal is to calculate the pressure drop in the system.

Is there a specific turbulence model to use for small diametre pipes ?

Thanks

[MRI]

Hello Farid,
k-eps should work. I think you have to look on your mesh. Try to calculate the distance of the first layer with that tool https://www.cfd-online.com/Tools/yplus.php and apply the wall distance of the first cell to your mesh.
If you consider y+ as 1 or smaller, then you should switch to the standard k-eps Model with Low y+ Wall Treatment. Generally you should avoid y+ Values between 1 and 30.
Best regard
mri