[ImmersedBoundary] Deformation of Immersed Boundary in foam-extend

Phil_ · August 21, 2015, 09:58

Hi Foamer's,

I'm working on the IBM in the foam-extend next release testing version (3.2).

Problem:

What to do if the IB is moving? -> Probably use the movePoints() stuff.
But what to do if the IB is also deforming?

Trying to assign the deformed boundary through a new tri-surfase (.stl/.ftr) and rebuilding the masks (createIbMasks.H) didn't work. The masks don't have the reference to the new IB-Geometry. I guess it's necessary to rebuild the mesh or at least the IB-Patch. Is this possible with an fvMesh or do I need to use a dynamicFvMesh?

Any pointer in the right direction is appreciated.

Best regards,
Philip

sanazm · August 2, 2016, 10:33

Hi Philip,
could you solve your problem? If yes, can you please share it with me?

Regards,
Sanaz

Quote:

Originally Posted by Phil_

Hi Foamer's,

I'm working on the IBM in the foam-extend next release testing version (3.2).

Problem:

What to do if the IB is moving? -> Probably use the movePoints() stuff.
But what to do if the IB is also deforming?

Trying to assign the deformed boundary through a new tri-surfase (.stl/.ftr) and rebuilding the masks (createIbMasks.H) didn't work. The masks don't have the reference to the new IB-Geometry. I guess it's necessary to rebuild the mesh or at least the IB-Patch. Is this possible with an fvMesh or do I need to use a dynamicFvMesh?

Any pointer in the right direction is appreciated.

Best regards,
Philip

Phil_ · August 2, 2016, 11:09

Hi Sanaz,

I went the dynamicFvMesh way and implemented a method for re-reading the .stl/.ftr file.

In order to update the IBM, the solver does an update() call to the mesh object of a class derived from dynamicFvMesh. Here a re-read Method is called that finally deletes the demand driven data of the immersedBoundaryFvPatch / immersedBoundaryPolyPatch and reads in the new .stl/.ftr to the triSurfaceMesh object. Now the sizes of all the fields have to be updated and the old fields have to be mapped onto them.

After the update(), the ibMasks can be created freshly through ibPatch.gammaExt() etc. in the solver.

I hope this gives you a rough impression. And no guarantuee that in any way it is efficient or smart to do it like this

Best regards,
Philip

sanazm · August 2, 2016, 11:29

Hi Philip,

Thanks for the reply.
I am new on OpenFOAM, so it is difficult for me to know what exactly you did. But the good thing is that I found that it is possible to consider IB deformation

I plan to use IBM in OpenFOAM, but (till now) that seems difficult for me, because I couldn't find an organized tutorial. I go through the folders and files to understand them, but it is time consuming

Regards,
Sanaz

August 21, 2015, 09:58	Deformation of Immersed Boundary in foam-extend	#1
Phil_ Member Join Date: May 2014 Posts: 40 Rep Power: 12	Hi Foamer's, I'm working on the IBM in the foam-extend next release testing version (3.2). Problem: What to do if the IB is moving? -> Probably use the movePoints() stuff. But what to do if the IB is also deforming? Trying to assign the deformed boundary through a new tri-surfase (.stl/.ftr) and rebuilding the masks (createIbMasks.H) didn't work. The masks don't have the reference to the new IB-Geometry. I guess it's necessary to rebuild the mesh or at least the IB-Patch. Is this possible with an fvMesh or do I need to use a dynamicFvMesh? Any pointer in the right direction is appreciated. Best regards, Philip

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August 2, 2016, 11:09		#3
Phil_ Member Join Date: May 2014 Posts: 40 Rep Power: 12	Hi Sanaz, I went the dynamicFvMesh way and implemented a method for re-reading the .stl/.ftr file. In order to update the IBM, the solver does an update() call to the mesh object of a class derived from dynamicFvMesh. Here a re-read Method is called that finally deletes the demand driven data of the immersedBoundaryFvPatch / immersedBoundaryPolyPatch and reads in the new .stl/.ftr to the triSurfaceMesh object. Now the sizes of all the fields have to be updated and the old fields have to be mapped onto them. After the update(), the ibMasks can be created freshly through ibPatch.gammaExt() etc. in the solver. I hope this gives you a rough impression. And no guarantuee that in any way it is efficient or smart to do it like this Best regards, Philip

August 2, 2016, 11:29		#4
sanazm New Member sanaz Join Date: Jul 2016 Posts: 5 Rep Power: 10	Hi Philip, Thanks for the reply. I am new on OpenFOAM, so it is difficult for me to know what exactly you did. But the good thing is that I found that it is possible to consider IB deformation I plan to use IBM in OpenFOAM, but (till now) that seems difficult for me, because I couldn't find an organized tutorial. I go through the folders and files to understand them, but it is time consuming Regards, Sanaz