[jd01930]

Hello all,

I am running a simulation of a Backwards Facing Step Combustor using ReactingFoam solver. Gas species prescribed at beginning of simulation are CH4, O2, N2,

I am trying to ignite it via energy injection using constant/fvOptions file and topoSet function in OpenFOAM-5.x. I initialized the flow field without energy injection and let the flow field with different gas species develop before turning on chemistry and reactions.

Recently I have been running it and after the energy injection is added it slowly climbs in temperature because I decreased my deltaT to 1e-7 seconds.

Energy injection begins at t=0.285 s at a level of h = 5e8 kg/m/s^3. It is supposed to inject energy until t=0.288 s.

The simulation continues to run satisfactory until t = 0.2861204 seconds.

There is no crazy spike in iterations calculated for U velocity. In the output it just says "Application 45971293 exit codes: 134
Application 45971293 exit signals: Killed
Application 45971293 resources: utime ~579s, stime ~153s, Rss ~129344, inblocks ~621642, outblocks ~0"


Then the error file says. "FOAM FATAL ERROR: Singular matrix
From function void Foam::LUDecompose(Foam::scalarSquareMatrix&,
Foam::labelList&, Foam::label&)
in file matrices/scalarMatrices/scalarMatrices.C at line 69.



I am wondering what the reason would be for this Singular matrix error that happens all of a sudden after running this for many thousands of timesteps. I have seen other forum posts where people have said that they would change their solvers in fvSolutions, but I am not sure how or why I would need to change this.


Any help is appreciated.

[Swirl]

Hi, were you able to solve this issue? I am currently running into the same error. Thanks in advance!