POLARIS 2-D calculation energy groups

[Charlie Karlson]

POLARIS in SCALE 6.2 will start with either the 252 or 56 group libraries.  However, I cannot find in the SCALE 6.2 User's Manual or the POLARIS output how many energy groups are used in the the 2-D MOC calculation.   No input cards seem to allow one to define those energy group either.  Did I miss it or is that documented elsewhere?  Thx, Charles

[BK Jeon]

Hi Charles, 

You can specify the library in the Polaris using "lib" card. 

Please refer to the Polaris manual : https://scale-manual.ornl.gov/Polaris.html#library-nuclear-data-libraries
Library information is also printed at the beginning of Polaris output. 

Please let me know if you have further questions.

Thanks,

BK,

2023년 12월 14일 목요일 오전 10시 49분 3초 UTC-5에 Charlie Karlson님이 작성:

[Charlie Karlson]

Sorry, I was not clear in my question.  I meant not the "lib" card libraries but rather what is the number of energy groups POLARIS uses in the 2D calculation after the micro group and resonance calculations are completed, then collapsed into for example <25 energy groups in the 2D lattice calculation.  I can find no mention of that in the user's manual.

[BK Jeon]

Dear Charlie, 

The actual number of energy groups used in the 2D Polaris MOC calculation is the same number of groups of each library. 

For example, if you're using the 56 group library, the Polaris MOC calculation will be done with the same 56G energy group structure. 

We are currently developing the on-the-fly group collapsing scheme (e.g., Polaris starts with the 56G for resonance (self-shielding) XS calculation, then reduces it to a small number of group before 2D MOC calculation) to enhance the efficiency of lattice calculation using the smaller number of groups instead of the library group structure, but this is still under the development and not available in the current production release.

Thanks,

BK

2023년 12월 15일 금요일 오후 1시 24분 37초 UTC-5에 Charlie Karlson님이 작성:

[Charlie Karlson]

That will be a good change, thank you!