We are attempting to run a CFD analysis of a aircraft propeller blade. The propeller and nacelle model is an exported IGES file from Pro/Engineer. We are having troubles creating a flow volume using the existing IGES file geometry in GAMBIT. We are following the tutorial supplied by Fluent; however it does not seem to appply to our case due to the complexity of our structure. Please advise about creating this flow volume if you have experience with this sort of problem.

Does the fact that we are exporting an IGES of an assembly pose a problem? Must we export an IGES file only from a part so that the file is seen as one solid piece (i.e. - no faces between assembled geometries)?

Thanks

You might find it easier to import your geometry to Gambit as an ACIS solid.

Is ACIS a export option for PRO/E? My version doesn't give me that option. I did find a converter program on the web to go from pro/E to acis but it wasn't free. What is the advatange of using an acis file?

Thanks for your help.

I used to have problems with IGES when trying to import geometry to Gambit. Problems like not being able to see faces. When I used ACIS, all lower geometries were recognised and showed as reals. Also, solid operations in Gambit are quite useful. You can import your basic solid and do the rest of your solid operations with Gambit. You'll find it convenient.

I have'nt worked with Pro/E before, but I understand Gambit can import from that package directly!

You can import from Pro/E "directly", but you have to have your system set up for it and it will not work on certain configurations.

No problem though. The direct import option is the equivalent of exporting the model from Pro/E as a VRML file and importing it into Gambit using, say,

import vrml "model.wrl"

What I do is to export the model as a STEP file and import the STEP file into Gambit. This has always worked well for me.

The step file has brought over real volumes but I was also able to do this with iges. I am in the processes now of trying to subtract it the propeller blade and nucelle from a rectangular volume. What order do you guys suggest doing this. mesh the faces of the the volumes and then subtract them, or subtract the volumes first then mesh, or mesh the vol then subtract? Thaks for all the help guys.

In the past with the iges files it would crash when trying to mesh the airfoil section or when trying to subtract.

Thanks again

Using step files I noticed that it was bringing all geometry in metric instead of the inches set up in proE. Is there a way to change the geometry to inches in gambit? Is this a normal problem? Still crashing though.

With regard to the order, you should always finish your geometry before attempting your mesh. As per the units, Gambit deals only with numbers. You define your units later in Fluent by scaling.

[jun005]

I also having the problem regarding running the propeller simulation....
May i get any guideline from anyone who success ran the simulation ?

Thanks....

[benji2642]

Hi all, and Jun005,

have u manage to run the propeller simulation?
Do u have any tips or advices to run it?

Thx, i 'll have to use it pretty soon

[CFD_4]

export as parasolid from pro/E.
Make a new volume in gambit.
substract the propeller volume from this big volume.
You will get flow volume.