Incorrect reaction rates reported for assemblies with symmetry factors!=1

[bsculac]

Incorrect reaction rates are reported for assemblies with symmetry factors. This is caused by components' volumes being reported at full value even when a block is partially outside the core. This effects the calculation of the integrated multigroup flux at either:

armi/armi/reactor/components/component.py

Line 1244 in 471e9e2

volumeFraction = self.getVolume() / self.parent.getVolume()

or

armi/armi/reactor/components/component.py

Line 1259 in 471e9e2

return pinFluxes[self.p.pinNum - 1] * self.getVolume()

Related discussion discusses some approaches to solving this issue. While it would be semi-nonphysical, reducing the calculated component volume by the symmetry factor of the parent objects like what is done here would likely solve the issue:

armi/armi/reactor/components/component.py

Lines 827 to 829 in 471e9e2

	volume = self.getVolume() / (
	self.parent.getSymmetryFactor() if self.parent else 1.0
	)

[john-science]

@bsculac So, I had trouble following your question in that the lines you were pointing to were no longer valid.

So, on GitHub, you can technically point to any line of code as you originally did:

https://github.com/terrapower/armi/blob/main/armi/reactor/components/component.py#L1244

But that points to a line in the main branch. And since you opened this ticket, that exact line number changed 5 times. So, on GitHub, we can navigate to an exact commit and put a reference in like this:

https://github.com/terrapower/armi/blob/471e9e247f0bcb113611596c358ba43c603fdca2/armi/reactor/components/component.py#L1244

And the benefit there is that it will actually render as the line of code you want to point to visibly, and as long as that commit isn't deleted (unlikely on a main branch), then it can never go stale:

armi/armi/reactor/components/component.py

Line 1244 in 471e9e2

volumeFraction = self.getVolume() / self.parent.getVolume()

Anyway. I tried to revive the lines you were referencing. Can you look and see if I got it right?

Thanks!

[bsculac]

I think that's correct, I am not sure what the original lines were but I think the meaning is captured!