How to Calculate Atom/B-cm Values for Nuclear Fuel Composition?

  • Thread starter Thread starter emilmammadzada
  • Start date Start date
  • Tags Tags
    Fuel Mcnp6 Mcnpx
AI Thread Summary
The discussion focuses on calculating atom/b-cm values for various isotopes in a nuclear fuel composition. The methodology involves determining atomic densities by summing atomic masses, knowing the material's density, calculating mass fractions for each radionuclide, and applying a specific formula. Participants express curiosity about the absence of fuel density information in the provided data and seek clarification on whether densities are calculated separately for different isotopes. The data originates from a Serpent nuclear code input file, highlighting the need for additional resources or references to fully understand the calculation process. Understanding these calculations is crucial for accurate nuclear fuel composition analysis.
emilmammadzada
Messages
129
Reaction score
19
TL;DR Summary
How to Calculate Atom/B-cm Values for Nuclear Fuel Composition?
Hello everyone,

I came across the following atom/b-cm values for a specific nuclear fuel composition:
U-234.81c 1.1369e-06
U-235.81c 3.0421e-05
U-236.81c 2.4896e-06
U-238.81c 0.019613
Np-237.81c 4.6686e-05
Pu-236.81c 4.97e-10
Pu-238.81c 0.00011695
Pu-239.81c 0.0022076
Pu-240.81c 0.0013244
Pu-241.81c 0.00019375
Pu-242.81c 0.00029277
Am-241.81c 0.00010791
Am-242m.81c 9.2989e-06
Am-243.81c 0.00010017
Cm-242.81c 5.625e-06
Cm-243.81c 5.4321e-07
Cm-244.81c 6.724e-05
Cm-245.81c 1.7397e-05
Cm-246.81c 9.2285e-06
Zr-90.81c 0.0037456629
Zr-91.81c 0.00081683844
Zr-92.81c 0.00124855430
Zr-94.81c 0.00126529876
Zr-96.81c 0.00020384560
Mo-100.81c 9.04954512e-05
Mo-92.81c 0.0001360496577
Mo-94.81c 8.53224251e-05
Mo-95.81c 0.0001474173129
Mo-96.81c 0.0001548471529
Mo-97.81c 8.89909086e-05
Mo-98.81c 0.0002256070916

I am curious about the methodology and formula used to calculate these atom/b-cm values. Could someone explain the process or point me to relevant resources or references?

Thank you!
 
Engineering news on Phys.org
To calculate the atomic density of a material, follow these steps

1 - add up all the atomic masses
2 - know the density of the material
3 - calculate the mass fraction for each radionuclide
4 - calculate the atomic density with the formula
((density*mass fraction*avogadro number)/total atomic mass)*1e-24)

5 - result in atoms/barn-cm
 
Reply
  • Like
  • Informative
Likes Astronuc, emilmammadzada and Alex A
Alexander Camargo said:
To calculate the atomic density of a material, follow these steps

1 - add up all the atomic masses
2 - know the density of the material
3 - calculate the mass fraction for each radionuclide
4 - calculate the atomic density with the formula
((density*mass fraction*avogadro number)/total atomic mass)*1e-24)

5 - result in atoms/barn-cm
Will each nuclide be written here as density or total density composition?
 
emilmammadzada said:
Will each nuclide be written here as density or total density composition?
Atom Densities
 
Reply
  • Like
Likes emilmammadzada
Alexander Camargo said:
Atom Densities
Isn't it separate for uranium and separate for neptunium in this composition?
 
emilmammadzada said:
Isn't it separate for uranium and separate for neptunium in this composition?
use the formula to reverse engineer this and get this answer, because just looking at the data like this, I can't tell. Do you have the density of this material?
 
Reply
  • Like
Likes emilmammadzada
Alexander Camargo said:
use the formula to reverse engineer this and get this answer, because just looking at the data like this, I can't tell. Do you have the density of this material?
I got this data from the serpent nuclear code input file. There was no fuel density given there, I just wonder how the content of such fuels is calculated. There is no information about density here
% --- 2D SFR Assembly based on MET-1000

% --- Materials

mat fuel sum tmp 807.15 vol 89.15304673765142 rgb 255 0 0 burn 1
U-234.81c 1.1369e-06
U-235.81c 3.0421e-05
U-236.81c 2.4896e-06
U-238.81c 0.019613
Np-237.81c 4.6686e-05
Pu-236.81c 4.97e-10
Pu-238.81c 0.00011695
Pu-239.81c 0.0022076
Pu-240.81c 0.0013244
Pu-241.81c 0.00019375
Pu-242.81c 0.00029277
Am-241.81c 0.00010791
Am-242m.81c 9.2989e-06
Am-243.81c 0.00010017
Cm-242.81c 5.625e-06
Cm-243.81c 5.4321e-07
Cm-244.81c 6.724e-05
Cm-245.81c 1.7397e-05
Cm-246.81c 9.2285e-06
Zr-90.81c 0.0037456629
Zr-91.81c 0.00081683844
Zr-92.81c 0.00124855430
Zr-94.81c 0.00126529876
Zr-96.81c 0.00020384560
Mo-100.81c 9.04954512e-05
Mo-92.81c 0.0001360496577
Mo-94.81c 8.53224251e-05
Mo-95.81c 0.0001474173129
Mo-96.81c 0.0001548471529
Mo-97.81c 8.89909086e-05
Mo-98.81c 0.0002256070916
 

Hot Threads

Recent Insights

Back
Top