Creation of example with nuclides heating in a homogenised material

[shimwell]

Occasionally we need the heating on components in a blanket.

Ideally there would be a detailed 3d model with all the blanket components separately defined as cell volumes.

As an early stage is is common to make a homogenised material with the seperate componets (e.g steel, coolant and breeder) mixed together into one material and assigned to one cell volume.

From this mixed material it can be useful to get a tally score (e.g. heating) on separate nuclides.

So we should add an example for this and I think the relevant openmc feature is Tally.nuclides =[ ]

https://docs.openmc.org/en/latest/pythonapi/generated/openmc.deplete.abc.NormalizationHelper.html#openmc.deplete.abc.NormalizationHelper.nuclides

A useful example is also here https://docs.openmc.org/en/latest/examples/tally-arithmetic.html

Adding layers to the model allows the score to be found per nuclide as a function of depth which can also be interesting

[bruceey42]

This would be a great enabler for early thermal-hydraulic design of blankets!