issue with surfaceFieldValue in v1912

I noticed an issue with surfaceFieldValue combination with dynamicMotionSolverFvMesh in v1912. The function writes out the header for all time steps into the dat file.

I upload the case as a zip file. case.zip

If you run it in v1812 the dat file in postProcessing is fine. If you run it in v1912 it writes out the header in each time step, however if you change in dynamicMeshDict "dynamicMotionSolverFvMesh" to "staticFvMesh", the output is fine again.

Please consider, that the case is a constructed one for this problem, so it has no real physical meaning.

assigned to @mark

unassigned @mark

This is (partly) by design; if the mesh points move or the topology changes the face selections are updated and feedback written to the log file (number of faces and area etc).

Currently we have do not have a check to see if the selected faces have changed after the mesh update to bypass re-writing the header information.

Ok, was it removed after v1812? It worked previously. What would be a solution?

Not removed - old code versions would fail for topological changes since the face sets were not updated on mesh changes.

Solution - to be determined. Ideally the header would only be rewritten if the face sets have changed, or perhaps add a user entry to only write the header once.

I see, I think the second option would be the easiest from a use perspective. An optional boolean entry (default false) in the function object definition maybe?

Sure - will push an update to the develop branch shortly

Great! Thank you.

mentioned in commit eb875079

I've pushed a potential fix to a new branch issue-1556-fo-header-writing under commit eb875079

There's a new optional updateHeader entry that defaults to yes to control whether the header output is updated. Can you test?

volFlux
{
    type            surfaceFieldValue;
    libs            ("libfieldFunctionObjects.so");

    writeControl    timeStep;//JN: we write out the volume flux into a text file
    writeInterval   1;//JN: we write out the volume flux every time step into a text file

    writeFields     no;
    log             true;
    regionType      sampledSurface;

    updateHeader    no; // NEW ENTRY - defaults to 'yes' if not given

    ...
}

If all OK I'll push out across the other function objects

Tested it, it works well. Thank you!

Dear @jnagy , would you please consider to close the ticket if you deem that the issue is resolved? Many thanks

Sure, sorry.

Is this already merged?

I don't know. I assumed so, as I was asked to close the issue.

A few crossed-wires - the code is not merged yet!

Please leave open for now

Is this still planned to be merged for this upcoming release?

mentioned in merge request !360 (merged)

mentioned in commit 7ee3ae2a

mentioned in commit 1b45599b

mentioned in commit 5863c94b

mentioned in issue #1942 (closed)

Code was merged in !360 (merged)

closed

mentioned in issue #2383