[topspin247]

Hi,

I was wondering if there is a way to specify a fan boundary condition on a surface in CFX, similar to the one shown here for Fluent:

https://www.sharcnet.ca/Software/Fluent6/html/ug/img1174.gif


The most important thing for me is modeling the swirling velocities at the outlet of the fan surface. Thanks.

[lgn_aero]

There is a method in CFX to simulate the fan BC but different from that is in fluent. The fan should be replicated as one element thick subdomain (same for fluent also) and then define the momentum siurces equivalent to the head change across the fan. Momentum sources are of r, theta and phi....

[topspin247]

Gotcha, I ended up using a momentum source. My momentum source is basically a part file that is imported into design modeler, and it is meshed as a fluid domain. Is that okay? There are multiple elements within the momentum source because my fan is pretty big.

[lgn_aero]

You are almost there..
In the cross section doesn't matter but in thick you must have only one element.

[helvas]

Hi lgn_aero;

I was looking a solution nearly same problem, i need to apply a rotating flow on a interface domain, i have CFX V14 and on CFX V14 you can apply mass flow rate, pressure change (both are normal to the interface area) or you can apply an expression at interface domain. I try to write an expression but couldn't figure out how to simulate a mathematical model of rotating flow using r, theta and phi... I'm very new on CFD.
I'm trying to modelling a flow which moves like a screw, rotate and traslate at the same time which shown in the picture. (swirling flow?)

Can you halp me about how to model it? or can you write a little sample expression?

Thank you allready and sorry for my english.