TRC; Hollow Conic Sections

Dear FLUKA experts,

I require a hollow cone for part of my configuration. However, when I nest one TRC within another, say cone_in inside of cone_out, defining the region as cone_out - cone_in, I always seem to get a warning about touching bodies. However, the same error is not present for spheres, nor does it occur
for cylinders. I should mention as well that the inner and outer TRC bodies are to have the same “height”, the inner one is identical, except for the radii scaled back slightly (though when I mess with the parameters, the warning persists).

Here’s a basic input file consisting of only two example regions, a sphere, and the problematic conic section:
cone.inp (377 Bytes)

Can I expect this to be a problem for my simulation? Is there a way to eliminate the warning?

Thank you,


Dear Regan,

the top surfaces of the cones are indeed touching. Since this position (z = 100 cm) is calculated from the base coordinates and heights, it can lead to geometrical errors due to numerical imprecision.
To avoid the issue you need to increase the height of the inner cone (even by a bit) to make it go over the outer one, as you did at the bottom.


Thank you, Dávid, this has resolved the issue.