[zacko]

Hello there,

I am working on a preliminary design tool in python for a centrifugal compressor. By now I was able to build a meanline model, generate a beta-angle distribution and transform the beta-angle into a theta-angle (wrap Angle) for 3D.
To import my model I wrote a script to write the coordinate, theta and thickness data to the .rtzt-file format for Bladegen.

When I import the file the first problem which occurs, is the cross over line (Figure 1). Usually Bladegen generates an Inlet- and Outlet Area but here this cross-over happens and I don't know why. Furthermore, when I correct the point at the shroud, the blade view won't generate anything good and a TE CutOff Error occurs (Figure 3). In Figure 2, you can see my theta-distribution and the recalculated beta-distribution by BladeGen.

I also tried to only use a theta-angle of 0.0 at any point to see what happens.
After importing, the cross-over problem occurs again. When I adjusted it the blade-view changes to figure 4. Which doesn't make sense at all.

I can only imagine that my theta-values may cause somewhere a problem, although the problems still occur with a constant theta of 0.0.
I rather would love to import my beta-data, so Bladegen can calculate the theta-distribution by itself although I used the given formular to calculate theta from beta.

I'm very thankful for any advice!

Thank you,

Daniel

[zacko]

Answer for similar questions in the future:

1) The control curve cross happened, because one Point on my shroud curve had a negative value and was therefore offset to the other points. Only saw it looking at the point data more clearly.

2) The Error TE Cutoff happened, because I always imported my point data in meters. The .rtzt-File contains the radial coordinate, theta-angle, coorindate in Z-direction and the thickness. Because I exported my points in meter and my thickness was in millimeter, Bladegen couldn't generate my blades. So, I switched from meters to millimeters in my .rtzt-File and every problem was solved!