# ‘Shared fission bank is full’ when running delpetion problem

**URL:** <https://openmc.discourse.group/t/shared-fission-bank-is-full-when-running-delpetion-problem/1212>\
**Category:** User Support\
**Created:** [May 18, 2021, 12:31pm UTC](https://openmc.discourse.group/t/shared-fission-bank-is-full-when-running-delpetion-problem/1212 "2021-05-18T12:31:23Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Chelsea](https://yyz2.discourse-cdn.com/free1/user_avatar/openmc.discourse.group/chelsea/32/1212_2.png) [@Chelsea](https://openmc.discourse.group/u/Chelsea)\
**Post date:** [May 18, 2021, 12:31pm UTC](https://openmc.discourse.group/t/shared-fission-bank-is-full-when-running-delpetion-problem/1212/1 "2021-05-18T12:31:23Z")

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Hi everyone,

When I run the depletion case, the k-eigenvalue simulation was stopped, and it says:

> WARNING: The shared fission bank is full. Additional fission sites created in this generation will not be banked.  
> free(): invalid next size (normal)  
> Aborted  
> While the k-eff is rather low, around 3000pcm.

The pincell depletion example [/pincell\_depletion](https://docs.openmc.org/en/stable/examples/pincell_depletion.html#Pincell-Depletion) works well. But when I changed the geometry and materials, it raised an error message. It only re-run the simulation 4 times, though I set the time steps and it should be modeled every 30 days over 6 months.

Greetings,  
Chelsea

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**Author:** ![HaoPF](https://avatars.discourse-cdn.com/v4/letter/h/ba9def/32.png) [@HaoPF](https://openmc.discourse.group/u/HaoPF)\
**Post date:** [June 1, 2021, 7:38am UTC](https://openmc.discourse.group/t/shared-fission-bank-is-full-when-running-delpetion-problem/1212/2 "2021-06-01T07:38:50Z")

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Dear che,

I’m a beginner in OpenMC, and after I build the model and run it, I get the same error.

When I lowered the number of particles in the setting.xml file, OpenMC worked fine again.I wonder if my limited computing ability is causing the problem.What do you think about that?

Thank you in advance for your help.

HaoPF

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**Author:** ![andrewjohnson](https://avatars.discourse-cdn.com/v4/letter/a/f14d63/32.png) [@andrewjohnson](https://openmc.discourse.group/u/andrewjohnson)\
**Post date:** [June 2, 2021, 3:21am UTC](https://openmc.discourse.group/t/shared-fission-bank-is-full-when-running-delpetion-problem/1212/3 "2021-06-02T03:21:30Z")

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Chelsea,

By

> It only re-run the simulation 4 times

do you mean the simulation only progressed through four time steps? If you have over depleted, there could be issues related to the multiplication factor being too low. This could be due to not enough fuel at a later point. A very low k-eff is tricky to handle and could be the cause of your fission bank issue.

Drew