Numerical Instability/segemntation error with Burn-Away Features in FDS

[BastianStahra]

Describe the bug I modelled a balcony with burnable objects.

Objects start to burn at an ignition temperature. After the fuel is exhausted the object burns away.

Numerical instability and segmentation errors appear after about 220s.

This happens when the objects are modelled through all meshes.

When you apply a hole at the boundary of a mesh, so that the burnable objects don't go through the meshes the numerical instablity and segmentation errors don't appear.

The balconies burn as they should.

To Reproduce Steps to reproduce the behavior:

1. Take the model "BurnAway-BA0016" and run it until around 250s --> error should occur
2. Take the model "BurnAway-BA0020" and run it until 3600. --> nor error occurs and objects burn away completely

Expected behavior I expect the balcony to burn away completely without errors even though objects are modelled through many meshes.

Screenshots see FDS-Files

Desktop (please complete the following information):

FDS/6.8.0_IntelComp_IntelMPI.2021.2_mkl

Linux Cluster PLEIADES Uni-Wuppertal

Additional context

Please see the FDS-Files. Add any other context about the problem here. 02-FDS.zip

[mcgratta]

Run your case with the latest version of FDS, 6.9.1.

[BastianStahra]

I did. My testcase works fine now. Thanks for the update!

=)

[mcgratta]

Good. I'll close the issue.