[captiosus]

Hello,

I'm analysing a cooling axial flow fan in a tube with a steady flow, incompressible. My mesh is not so bad (0.79 max skewness) but I get some issues.

My static and total pressure is always decreasing (it has to increase static pressure) in the tube even I changed boundary conditions like
-Pressure Inlet - Pressure Outlet with target mass flow rate
-Velocity Inlet - Pressure Outlet

Also, area-weighted average velocity in input and output are very different, like 2 times bigger in output.

I checked the rotating zone but it seems ok. My model is standard k-eps and I use coupled methods.

Where should I check again? What do you think?

Also, what boundary conditions should I use?

Lastly, Can you share or link some documents about this problem with keywords like cooling fan, boundary conditions in fan analysis? I made literature research but I think that you already did and solved some cases, so your orientations are valuable for me.

Thank you so much! Have a good day!