Search found 560 matches

by Ana Jambrina
Thu Oct 07, 2021 11:37 am
Forum: Users
Topic: Problem with branch card
Replies: 1
Views: 67

Re: Problem with branch card

The ' coef ' card creates a multi-dimensional coefficient matrix, not a burnup-dependent sequential variation. Check the description of the Automated burnup sequence , more precisely the ' Setting up the coefficient matrix ' section. (Input options related to the automated burnup sequence: ' casemat...
by Ana Jambrina
Wed Oct 06, 2021 3:38 pm
Forum: Users
Topic: Most simple way of constructing an geometry of infinte assemblies
Replies: 3
Views: 72

Re: Most simple way of constructing an geometry of infinte assemblies

You can play with how you define the surfaces infinite/finite and how you apply the boundary conditions. Different setups could formulate equivalent models.
Check the section Collection of example input files and the Tutorial to familiarize yourself with these concepts.
by Ana Jambrina
Wed Oct 06, 2021 3:02 pm
Forum: Users
Topic: Most simple way of constructing an geometry of infinte assemblies
Replies: 3
Views: 72

Re: Most simple way of constructing an geometry of infinte assemblies

Lattice within a lattice (lattice(s) lev_1: pins —> fuel-assembly, lattice lev_2: fuel assemblies —> mini-core). Alternatively, you could directly go from the pin definition to the mini-core. How you define the geometry is completely up to you - Serpent structures/levels aim to help out with the con...
by Ana Jambrina
Sun Oct 03, 2021 11:38 am
Forum: Users
Topic: Inconsistent particle XS values from detector between averaged tally and individual tally
Replies: 10
Views: 225

Re: Inconsistent particle XS values from detector between averaged tally and individual tally

Based on the data provided, a rough estimate (and not fully consistent) of the 'homogenized/averaged' microscopic cross-section for U-238 radioactive capture of the fuel compacts (Ebin 40: [6.53014E-06, 6.69545E-06]) is ~1.33E+03 (not considering uncertainties).
by Ana Jambrina
Sat Oct 02, 2021 10:34 pm
Forum: Users
Topic: Inconsistent particle XS values from detector between averaged tally and individual tally
Replies: 10
Views: 225

Re: Inconsistent particle XS values from detector between averaged tally and individual tally

As an example of my previous comment: - He31_DH_1: DET1 (Ebin 40) rel error = 0.00329 - He31_DHavg: DET1 (Ebin 40) rel error = 0.00053 ** ‘heterogeneous --> He31_DH_1’ as with a different definition of the fuel material f1, f2,…, f31, ‘homogeneous --> He31_DHavg’ as the same definition of the fuel m...
by Ana Jambrina
Sat Oct 02, 2021 1:11 pm
Forum: Users
Topic: Inconsistent particle XS values from detector between averaged tally and individual tally
Replies: 10
Views: 225

Re: Inconsistent particle XS values from detector between averaged tally and individual tally

Start by having a converged solution - and estimates with an associated variance within the same order of magnitude. You can see from the flux how off the calculation is for the ‘heterogeneous fuel compact' calculation.
by Ana Jambrina
Fri Oct 01, 2021 4:09 pm
Forum: Users
Topic: Reflecting lattice stack
Replies: 3
Views: 60

Re: Reflecting lattice stack

If you have a problem with the geometry that is not obvious and the plots do not help, maybe try to simplify the geometry and progressively add new items (or vice-versa), that way, you might be able to track down what is causing the problem.
by Ana Jambrina
Fri Oct 01, 2021 12:57 pm
Forum: Users
Topic: Inconsistent particle XS values from detector between averaged tally and individual tally
Replies: 10
Views: 225

Re: Inconsistent particle XS values from detector between averaged tally and individual tally

Aside the number of particles (and geometry definition - materials), as Ville pointed out, you are defining “derived” tallies: you calculate the XS by dividing two detector tallies (RR/flux) - check the statistical properties.
by Ana Jambrina
Fri Oct 01, 2021 12:55 pm
Forum: Users
Topic: Reflecting lattice stack
Replies: 3
Views: 60

Re: Reflecting lattice stack

Check the geometry: use the ‘plot’ option to help you out.
by Ana Jambrina
Fri Oct 01, 2021 1:11 am
Forum: Users
Topic: Inconsistent particle XS values from detector between averaged tally and individual tally
Replies: 10
Views: 225

Re: Inconsistent particle XS values from detector between averaged tally and individual tally

For clarification: the statistics, mean and relative error differences lie on the detector definition (scoring process) - both evaluation are not equivalent.