Understanding the mechanism of region rotation

User Support
1

Hello,

I’m new to the OpenMC community and am trying to create geometric scenes that enable me to rotate specific regions to simulate measurements campaigns. I’m trying to apply rotations to regions and not cells filled with universes, like I saw in the documentations. In doing so, I was faced with an issue regarding the bouding box of the rotated region. You can see the problem for yourself on the screenshots, the bounding box corners go to the infinity. I observed that this is not a problem at all for simulations, it works perfectly.

It is however a problem for me because I use handmade functions to create 3D plots of the scene by using the bounding boxes to precisely locate it and thus improving the resolution of the image.

I want to know if I’m doing something wrong or if this is a known bug that will be fixed in a future version.

Thank you !

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2

I thought about rotating each bounding box manually, but I would like to know if there is a better way. I also intend to use bounding boxes to handle the redefinition of emission sources automatically after rotation. If I’m not mistaken, the source variable source.constraint has to be changed after a rotation. Let’s say that my source is defined a a cylinder that is non emissive except for a few little spherical cells inside it, I want to set source.constraints on those little cells. But if I rotate my overall source (cylinder + inner spherical regions), I may have to redefine source.constraints to the new rotated spherical regions.

Am I right?