# Burn-up calculation different materials

**URL:** <https://openmc.discourse.group/t/burn-up-calculation-different-materials/3796>\
**Category:** User Support\
**Created:** [January 3, 2024, 9:23pm UTC](https://openmc.discourse.group/t/burn-up-calculation-different-materials/3796 "2024-01-03T21:23:00Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![daan1392](https://avatars.discourse-cdn.com/v4/letter/d/5daacb/32.png) [@daan1392](https://openmc.discourse.group/u/daan1392)\
**Post date:** [January 3, 2024, 9:23pm UTC](https://openmc.discourse.group/t/burn-up-calculation-different-materials/3796/1 "2024-01-03T21:23:00Z")

</div>

Hi all,

I am running a depletion calculation with lots of different materials and need to determine the burn-up of each material at the end of irradiation and would like to confirm my method of working.

I run the calculation using _normalization\_mode=‘fission-q’_ in the CoupledOperator (Not sure if I should use “energy-deposition” mode?). Then I tally the heating scores of each depletable material H and convert these to J/source: H'=H\cdot 1.602\times 10^{-19}.  
After which I determine the normalization factor f by dividing the total power given to the integrator P by the sum of all heating tallies \sum\_{mat-depl} H' from ‘tallies.out’.  
Then I can calculate the burn-up using: BU [MWd/tHMi]= \frac{H'\cdot f \cdot t\_{irr}}{m\_{HMi}}

Is this correct? I know there will be discrepancies due to not taking photon transport into account, but I am not yet interested in this. Thanks for helping me out.

---

<div class="post-metadata">

**Author:** ![daan1392](https://avatars.discourse-cdn.com/v4/letter/d/5daacb/32.png) [@daan1392](https://openmc.discourse.group/u/daan1392)\
**Post date:** [January 11, 2024, 10:13am UTC](https://openmc.discourse.group/t/burn-up-calculation-different-materials/3796/2 "2024-01-11T10:13:42Z")

</div>

It is clear to me now. I have to use _normalization\_mode=‘energy-deposition’_ and because it is a neutron only calculation, the _‘heating-local’_ tally should be used. Excuse me for the confusion as it is clearly explained here: [Energy deposition](https://docs.openmc.org/en/stable/methods/energy_deposition.html)