Hello! How can I create 2D- axisymmetric model mesh in Star CD with R-Z coordinates? Say, as example- simple tube.

I looked at the question of Anindya

http://www.cfd-online.com/Forum/star....cgi?read=1183

but it looks confusing, since taking cylindrical-2 co-orditate system suggests R and Theta as coordinates, but not R and Z. May be its possible to redefine somewhere to R-Z instead of R-Theta? Thanks a lot for any suggestion.

Vitaliy.

There is no 2D mesh posibility in Star. The only way to run "semi-2D" cases is to make a 3D mesh with onlz one cell layer in the third direction.

The easiest way to make the mesh in any coordinate system is to use StarGUIde. Go to create mesh -> 3D, select the proper csys (number 2 in your case) and give start and end coorinate for r, phi and z. For the number of cells in r, phi and z you should give 1 for the third dimension.

Thank you, Sven!

This is the way we tried allready, but our simple-physics-problem does not convereged, while in "quasi 2D" but without axial symmetry (csys number 1) it convereges fast.

I guess : 1 - cyclic boundary conditions must be set on both faces, which are perpendicular to phi

2- W-velocity component must be included in solution

If this in csys 2 then you don't need to solve for V (tangential), but should solve for U and W i.e. radial and axial. You only need cyclic boundary conditions if you have swirl, then you would need to solve for V also, as you have a 3-D problem

allan

A model with R-Z coordinates was created and cyclic boundaries on the two faces of the model was created. But while checking the boundaries it displays an error with number 27 Cyclic boundaries are not matched.

I would like to know the reason for this error and alternative to avoid this error,

Thanks

Vitaliy Pavlyk