Branch capability

User feedback and discussion on methods for group constant generation in Serpent 2
Post Reply
User avatar
Jaakko Leppänen
Site Admin
Posts: 2446
Joined: Thu Mar 18, 2010 10:43 pm
Security question 2: 0
Location: Espoo, Finland

Branch capability

Post by Jaakko Leppänen » Sun Jun 15, 2014 3:30 pm

The branch-card, as described in the memo, has currently the capability to apply three types of perturbations:

1) Change the temperature and density of a material
2) Replace one material with another
3) Replace one universe with another

Since it is up to the user to apply these capabilities to get the desired effect, it is not clear to me whether or not this capability is sufficient for all types of branch calculations. I can come up with ways to use these capabilities to do things like:

- Change the coolant density, temperature or boron concentration
- Change the fuel temperature
- Insert control rods

From the feedback I understood that it would also be convenient to model things like replacement of a damaged fuel pin or change in geometry due to assembly bow. Changing a fuel pin can be accomplished using the universe replacement option. I'm not familiar with the effects of assembly bow, but changes in lattice pitch could be invoked using the same card. In both cases these effects would be instantaneous, though, and not carried through the burnup simulation (this would require similar methodology for history calculations).

If you can think of branches that cannot be modeled using the options above, let me know.
- Jaakko

Post Reply