Is it possible to use TR or TRCL to translate an F4 or FMESH4 tally in MCNP6.2?

[19matthew89]

TL;DR

Is it possible to use TR card to translate a segmented or a mesh tally?

Hi everyone,
I'd like to know if it is possible to use TR or TRCL to translate an F4 or FMESH4 tally.

Let me better explain: I have a cell, centered at 0,0,0 and for this cell I set up a segmentation tally along z-axis with a series of planes orthogonal to the z-axis. Moreover, I have also set up a Cartesian mesh tally with FMESH4.
Now I'd like to translate the cell along the z-axis (and later also rotate). This can be done easily with TRCL card but may I apply the same transformation to the F4 segmented tally and FMESH4 tally that I set up for the cell at 0,0,0? so that, for instance, I do not need to define planes orthogonal to the z-axis or the mesh at different heights but such that the tallies on the translated cell inherit, somehow, the structure of the original tallies?

The section of the manual about tallies in repeated structure is mainly focused on lattices or elements of the universes and not about segmentation or meshes.

Thanks in advance

 

[Grelbr42]

You don't use the TR card to move the FMESH. You use the origin and axis entries on the FMESH. That let's you specify the origin of the mesh, the x-axis of the mesh, and the orientation of the mesh y-axis relative to the x-axis. If you were doing a cylindrical mesh then you specify the z-axis of the cylinder and the location of the zero of angle around the cylinder.

Note: Read the manual about the bounds of the FMESH very carefully when you are using this feature. Try it out a few times on runs with very small number of particles. The manual is kind of confusing, at least for me, on how the bounds are affected by the origin.

 

[19matthew89]

You don't use the TR card to move the FMESH. You use the origin and axis entries on the FMESH. That let's you specify the origin of the mesh, the x-axis of the mesh, and the orientation of the mesh y-axis relative to the x-axis. If you were doing a cylindrical mesh then you specify the z-axis of the cylinder and the location of the zero of angle around the cylinder.

Note: Read the manual about the bounds of the FMESH very carefully when you are using this feature. Try it out a few times on runs with very small number of particles. The manual is kind of confusing, at least for me, on how the bounds are affected by the origin.

Yeah! I already got in that kind of situation with the origin so now I know how to deal with that Indeed for mesh tally I already did and it was fast enough and not a big deal.
It would be more useful in the case of the of F4 tallies. With my current setup everything is anyway pretty easy but, but I'm afraid it might be a bit more bothersome when cells are going to be tilted.

 

[lauraB]

Hi 19matthew89,

your post about the "trans" coomand was very interesting for me!
Please, could you suggest a way to combine linear and rotated tallies?

Thank you
Laura

 

[19matthew89]

Hi 19matthew89,

your post about the "trans" coomand was very interesting for me!
Please, could you suggest a way to combine linear and rotated tallies?

Thank you
Laura

Hi Laura,
I don't exactly understand what you mean...
Every TR card (which has to follow a TRANS key word) is to be defined with a linear displacement vector:

TRn o1 o2 o3 xx’ yx’ zx’ xy’ yy’ zy’ xz’ yz’ zz’ m

with o1, o2, and o3 displacement vector.

Is this that you mean with "linear and rotated tallies"?

Cheers