CFD Online Discussion Forums

CFD Online Discussion Forums (
-   FloEFD, FloWorks & FloTHERM (
-   -   Problems with simulating an impeller (

Hannes September 4, 2008 08:50

Problems with simulating an impeller
hey everybody, I will explain in some words my prob. I try to simulate a radial fan. I designed the housing and the impeller. As boundary I layed on both outer surfaces static pressure and let the impeller rotate with moving wall-type rotate and set rpm. The calculation run good but the results were too small. I know the volume flow rate in accordance with the rpm from the fan. I tried a lot settings but it will be the hole time the same prob. So, has anybody did a simular project? I work with EFD.Lab V5.1 and solid works

Murat September 4, 2008 09:31

Re: Problems with simulating an impeller
How to model radial fan? Moving walls or rotating region? Is your impeller like disk or what?

Could you explain?

Hannes September 4, 2008 09:50

Re: Problems with simulating an impeller
okay, I selected the faces of the impeller, which geometry are comming from the cad-modell(the rotorblades look like the inner of a pump, surfaces radial orientated..), and lay the boundary condition moving wall on it- motion type is rotation. the rotation axis is correct and the rpm too.

Hannes September 4, 2008 11:47

Re: Problems with simulating an impeller
maybe this problem could be type of the turbulent solving of efd.lab.... I know ansys fluidmechanic got special solver for this?????????????????????

Murat September 5, 2008 03:00

Re: Problems with simulating an impeller
I think you should use the rotation region tool which is in EFD. First you should select local rotation in pyhsical feature. Then you create a solid like cylinder for impeller. Creating solid must have same geometry or same boundary like impeller.

If you create solid like impeller you can use the rotation region tool. EFD is not same Fluent I understant.

You can use moving wall for thin, like radial disk in EFD. For impeller you should use rotation region tool.

It is not related with turbulent.

Hannes September 5, 2008 03:02

Re: Problems with simulating an impeller
okay thanks, I will try this now..

Hannes September 5, 2008 06:41

Re: Problems with simulating an impeller
I can find the boundary condition moving wall, but I donīt find moving region. I work with V5.1, could it be that this option just working in a newer release???

jeremyli September 15, 2008 23:06

Re: Problems with simulating an impeller
You should create a region used to define rotating parts. So you should go through the tutorial of EFD.V5 you will find the steps to define such case as impeller.

Ive September 17, 2008 09:05

Re: Problems with simulating an impeller
To enable rotation, you must select the "Enable rotating reference frame" check box and specify the angular velocity on the "Rotating reference frame" step of the Wizard. In this case the whole model is considered as rotating. After finishing the Wizard, specify the Stator Real Wall boundary condition on all non-rotating walls of the model. This type of global rotation is applicable only for models which are completely axisymmetrical. If the model is not axisymmetrical, you should use local rotating regions available starting from version 7.0 Also you can see the Rotating Impeller tutorial (the last example in the version 5.1 Tutorial).

All times are GMT -4. The time now is 22:47.