How to Handle WIMS Reactor Physics Codes for Radial Neutron Flux Analysis?

AI Thread Summary
The discussion focuses on performing WIMS reactor physics code analysis for radial neutron flux by dividing fuel pins into equal-volume sub-regions and conducting criticality calculations. The user seeks advice on obtaining radial fast and thermal neutron flux, noting that the output file does not display the required two-group flux. Specific input files for the WIMSBuilder are shared, detailing fuel, clad, and coolant materials, along with their compositions and densities. Additionally, the user highlights the importance of correctly setting the energy cut-off and group split in the .route file to ensure accurate flux output. The conversation emphasizes the need for proper configuration to achieve the desired results in neutron flux analysis.
PhotonEd
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Hello hope someone can help me
I need to do WIMS reactor physics codes analysis for
1) divide fuel pin into radial equal-volume sub regions
2) preform criticality calculations to obtain radial fast and thermal neutron flux (use 0.615eV energy cut off between fast and thermal regions)
I will need advise on obtaining flux for the regions as the output file is not showing the 2 group flux, please see the below for some of the input files, many thanks

regards

1) equal section setup as below in .pwrpin file for wimsbuilder

FUEL MATERIAL 1
DENSITY 10.40
TEMP FUELTEMP
COMPOSITION \
U235 1.0997472E-03 \
U238 2.1525591E-02 \
U234 1.0409077E-05 \
U236 3.2482827E-07 \
O 4.5272144E-02

FUEL MATERIAL 2
DENSITY 10.40
TEMP FUELTEMP
COMPOSITION \
U235 1.0997472E-03 \
U238 2.1525591E-02 \
U234 1.0409077E-05 \
U236 3.2482827E-07 \
O 4.5272144E-02

CLAD MATERIAL 3
DENSITY 6.5
TEMP CLADTEMP
COMPOSITION Zr 100

COOLANT MATERIAL 4
DENSITY COOLDENS
TEMP COOLTEMP
COMPOSITION H 11.18983 O 88.81017

ANNULUS 1 RADIUS 0.40950 MATERIAL 1
ANNULUS 2 RADIUS 0.42950 MATERIAL 2
ANNULUS 3 RADIUS 0.47500 MATERIAL 3
ANNULUS 4 MATERIAL 4

2) for energy cut off and group split in .route file

....
ifelse(BRANCH,YES,[CRITIC 8 5],[CRITIC 2 5])
buckling 6 0.00022314 0.000065641 0.00001 0.0
begin
COND 5 6
energy 0.615 *This is for the Energy cut-off (2-groups)
begin
SMEAR 6 7
newmat 1 allm
begin
EDIT 7
groups SPLIT * this is to print for 2 grroup
nuclides Pu239 Pu241
...
 
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To anyone of interested
EDIT should be on card 6 before SMEAR as otherwise it will just print out the "smeared" 1 group (1 group) and not the 2 groups (fast ad thermal) as required
codes as of the below
:)

...
ifelse(BRANCH,YES,[CRITIC 8 5],[CRITIC 2 5])
buckling 6 0.00022314 0.000065641 0.00001 0.0
begin
COND 5 6 * Energy cut-off (2-groups)
energy 0.615 0 * Energy cut-off (2-groups)
begin * Energy cut-off (2-groups)

EDIT 6
groups SPLIT * print option for 2gr
begin

SMEAR 6 7
newmat 1 mat 1
*newmat 1 allm
begin
...
 
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