idaholab / moose

Multiphysics Object Oriented Simulation Environment
https://www.mooseframework.org
GNU Lesser General Public License v2.1
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Projection transfer randomness #20960

Open GiudGiud opened 2 years ago

GiudGiud commented 2 years ago

Bug Description

We (@muelcm and I on separate inputs) have observed that steady state calculations restarted into transients exhibit non deterministic behaviors in the projection transfers. The integrals of power density (transferred quantity) change between two consecutive runs At least in my inputs, I have made sure the variable types do not change in between the simulations so it's not this expected mode of failure.

Steps to Reproduce

Use fixed mesh on an exodus restart iirc might still trigger without fixed_mesh

Impact

Affects simulation results. Since the norm of the field is different, it's not that hard to realize there is an issue.

GiudGiud commented 2 years ago

Related blue_crab issue https://hpcgitlab.hpc.inl.gov/idaholab/blue_crab/-/issues/42