Perpendicular Flap tutorial - zero flap displacement

Hi All,

I am trying to run the Perpendicular Flap tutorial. Everything seems to be setup correctly and the run completes to the end without any errors, the fluid field also is calculated for all time steps (however, with zero flap displacement). I am using fluid-openfoam and solid-openfoam and the current version of openfoam-adapter was built successfully.

The resulting displacement field remains zero throughout and the flap does not move at all.
I get this warning in the output

A sub-vector in the residual-sum preconditioner became numerically zero ( sub-vector = 0). If this occurred in the second iteration and the initial-relaxation factor is equal to 1.0, check if the coupling data values of one solver is zero in the first iteration. The preconditioner scaling factors were not updated for this iteration and the scaling factors determined in the previous iteration were used.

Any idea what may cause this?


Hi @sinah,

the tutorial works correctly for me with OpenFOAM v2206, preCICE v2.5.0, and the adapter v1.2.1.

Which OpenFOAM version are you using? Anything else that could be special in your system?

At which time do you get this warning? This would mean here that you are always computing the same force/displacement. I assume you have not changed anything in the tutorial files.

Note that, after you make it work, in ParaView you will immediately see the fluid case moving, while for the solid case you will need to apply a warp-by-vector filter.

Thanks for your response. Using OF v2106 nothing particular about the system except that running it on an HPE system with their own version of MPI.

All the displacements come out as zero, even with the gnuplot tool provided with the tutorial, the displacement only shows a straight zero line.

Nothing changed and the warning comes after a two iterations.

Do other tutorials run? Does the elastic-tube-1d run? Does the flow-over-perpendicular-flap run with meaningful results?

I can run the quickstart one and works just fine, but for some reason seems Perpendicular Flap is not exchanging the data correctly… . Will also try the elastic-tube-1d

If the Quickstart is running, then maybe there is something strange with solidFoam.

Just to confirm: you are using solid-openfoam, not solid-solids4foam, right?

Yes running solid-openfoam and not solid-solids4foam