How to Declare a Spherical Neutron Source for Thermal Neutron Flux Calculation?

AI Thread Summary
The discussion focuses on the configuration of a simulation involving neutron sources and cell definitions. It highlights the importance of correctly setting the input parameters, particularly the impact line and source location, to avoid issues with edge placements. Suggestions are made for simplifying the source configuration, such as using a surface source instead of a complex geometry. Additionally, formatting corrections for the input file are recommended to facilitate better understanding and troubleshooting. Proper setup is crucial for accurate simulation results in neutron transport problems.
Addali sabah
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how I can declare a spherical neutron source to calculate the thermal neutron flux in a cell
c Created on: Tuesday, September 05, 2023 at 11:26
1 1 -1.58 -1
2 0 -2 #1
3 0 -3 #1 #2
4 0 3

1 rpp -0.5 0.5 -0.5 0.5 0 0.1
2 so 10
3 so 15

mode n
m1 15000. 0.12951 $matrix
6000. 0.01731 12000. 0.00546 11000. 0.008
20000. 0.35857 13000. 0.002184 8000. 0.40146
16000. 0.0118 26000. 0.0026 14000. 0.0101
imp:n 1 1r 0 1 $ 1, 4
sdef cell=2 rad=d1 erg= 0.025 par=1
si1 0 10
f4:n 1
e4 1.01e-10 121i 0.025
nps 10000
 
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A few things to think about,

The void cell is 4, so your imp line should be 1 1 1 0 not 1 1 0 1, right?

You have a point source at 0 0 0 (default source location) is this on the edge of two cells? It needs to not be on the edge. If you want to make cell 2 a homogeneous source, a sphere with a box cut out of it, that is tricky. A surface source might be easier from surface 2, but it depends a lot on what the problem is.

erg= has a space before 0.025

If you rename your input file to add .txt you can attach it to a post, or you can paste into BB code tags, then we can see the version with the correct formatting.
 
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Likes Greg Bernhardt and berkeman
Thank you sir for your comments
Cell 1 is immersed in a thermal neutron source which is the cell 2
 

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