I have to generate helical vanes of rectangular cross section for swirler. Though I got approximate curve by projecting a line on cylinder with angle equal to helix angle, I have not been successful in creating a geometrically correct helix. And also I have no clue for doing that. Can somebody help me?

Thank you in advance. Prasad

Hi,

to my knowledge there is no way to do that rigorously, one has to approximate the required helix using point translations and rotations or line projections. But after all, this should not be such a problem as we don't have curvilinear finite volumes in Fluent anyway...

Anyway, I'd be happy to be wrong, if anyone knows better.

George

Yaah, to some extent you're right, George! I thought that somebody who is using Turbo tool in Gambit might have some idea of generating a curve satisfying some equation.

On the other hand, very often we come across creating curvilinear shapes e.g. helical vanes in air swirler, the one I'm working with. If we approximate the curve then it has to be divided into different segments which makes meshing more difficult than meshing with a single line which connects two vertices following some rule. In case of many segments, we can join them by Line Merge function. But then the volume become virtual making further changes impossible.

Thanking you for your thoughts! Prasad

Why not create it in Pro Engineer or Autocad and import it into Gambit. This technique works really well. Give it a go!

one way to do is, imagine that u have the curve that represent the centerline of the helix u want to make,

now creat a rectangluar cross section that u want for the helix, and there is an option called swep face to make a volume , here chose these two things and create the volume u want .. easy i guess

for me, the best way to bild the solids to be mesh in Gambit is to use AutoCad and save the solids or regions a a *.sat file. I had a problem when I tray to build a helix in Autocad (in order to simulate a desublimator with a helix saparator), so I did it with Bentley Modeler (from Microstation) y save it as a *.sat file, it was quick and easy. Best Regards, Diego