[dskoutel]

Hello everyone

I want to share a problem i m facing with openFoam dynamic
meshing while trying to perform FSI simulations.

I m importing new boundary conditions- displacements/velocities from an external FEM solver and put them to the appropriate pointDisplacement/pointMotionU file, depending on the solver i choose. Curiously after the mesh.update() is executed i get a mesh that does not quite follow the new boundary conditions...(?)

I tried with simpler deformations and it turns out that it would only work whenever the boundary condition at the specific moving patch is uniform.

Did anybody have such a problem before or has any advice for me?

[lakeat]

What did you mean by saying "uniform"?

[dskoutel]

by uniform i mean sth like:

solidBody
{
type fixedValue;
value uniform (0.1 0.1 0);
}

Problem starts when the boundary condition in non uniform so instead i input a list of vectors.

[lakeat]

Hmm.., why did you use fixedValue patch, and not using the sixDoF... patch?

[dskoutel]

sixDoFRigidBodyDisplacement is not availiable in version 2.0 i think. I used fixedValue following the icoFsiFoam way.

[lakeat]

You mean,

OpenFOAM-2.x/src/postProcessing/functionObjects/forces/pointPatchFields/derived

???

[dskoutel]

no i mean

--> FOAM FATAL IO ERROR:
Unknown patchField type sixDoFRigidBodyDisplacement for patch type patch

Valid patchField types are :
24
(
angularOscillatingDisplacement
angularOscillatingVelocity
calculated
cyclic
cyclicSlip
empty
fixedNormalSlip
fixedValue
mixed
nonuniformTransformCyclic
oscillatingDisplacement
oscillatingVelocity
processor
processorCyclic
slip
surfaceDisplacement
surfaceSlipDisplacement
symmetryPlane
timeVaryingUniformFixedValue
uniformFixedValue
value
waveDisplacement
wedge
zeroGradient
)

[lakeat]

But surely you can load the .so file to add the new patches.

[dskoutel]

hmm ok loaded genericPatchFields library but i get some runtime errors...guess i need to check some stuff first. do u have any fsi solver in mind that actually uses this 6dof patch? i only saw it on pimpleDyMfoam but it doesnt seem to help much...

thanks for your help !

[lakeat]

pimpleDyMFoam can do the job. And sicDoF b.c patch is in another .so library, load the correct one.