How to model a truncated cone having two radius.

I have a question on how OpenMC handles the geometry of truncated cone having two radius? attached is the sample. Can anyone help me with an example? Thank you.

truncone3.jpg

Dear Sharif,
If you don’t have enough parameters in common functions, you can always use “General quadric surface”.
In your case, the type equation should be enough:
A(X-X0)**2+A(Z-Z0)**2+R(Y-Y0)**2=0
or
(X-X0)**2+(Z-Z0)**2+R(Y-Y0)**2=D

Calculate A so you can have a r at the height of h

Adding on to this here, it should be sufficient to use an XCone/YCone/ZCone, and then just add two planes to cut off the cone at the appropriate radii. If your cone is not parallel to one of the axes, then you can use the Quadric surface as suggested by Illia.

Best,
Paul