Is Immersed Boundary Method already available in OF 2.1.x or 2.2.x
Hi Foamers,
I just wonder, is IB (Immersed Boundary) method already integrated in OF 2.2.x (or OF 2.1.x), or just available with 1.6ext version? Also I am interested in VOF + IB method, can someone recommend related journal papers on the multiphase flow (VOF or similar) with IB method? Thanks a lot. Best regards, David 
Hi David,
AFAIK the IBM method is not available on "standard" OF versions. This post could help u out  meshless Regards, 
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Hi,
of course it is possible. It may take longer than implementing it from scratch, though, as there are thousands of changes to be made. OpenFOAM has changed a lot from version 1.6 to 2.x : some methods have disappeared and have been substituted by others, some of them are now called using other syntax, and so on. Good luck! Pablo 
Hi keepfit,
It will be nice if you succeed compiling an working version of IBM for 2.x. I already tried, but then I just realized that I was not able to sort out all the problems. I am looking forward for your success story :) ! Regards, 
Fictitious domain method in OF
Hi Foamers,
Instead of implementing IB method in OF 2.1.x/2.2.x, a so called fictitious domain (FD) method is used to present solid phase in fluid domain. Compared to the original IB method in OF1.6ext that inside the immersed boundary the p/U/alpha1 field is void and the BC is fixed, the fictitious domain (FD) method treats the immersed body as fluid, plus a rigid constraint (D(U)=0) to force the "fluid" inside IB boundary behaviour as rigid body. This new solver currently works fine in general (needs improvement), here is some rough results: A solid ball drops from air into water 1. Initial status http://31.media.tumblr.com/0c9d5927c...saho1_1280.png 2. ball dropping into water http://25.media.tumblr.com/c07c01121...saho2_1280.png 3. airwater interface after ball dropped into water http://25.media.tumblr.com/341011eb8...saho3_1280.png 4. Fictitious domain U field (ball is slowed down in water due to the drag force) http://24.media.tumblr.com/a98ddc20d...ho4_r1_500.png Cheers, David 
Hi keepfit,
Pretty interesting approach! Have you tried to model external flows with this methodology...flow around a profile or sphere. It would be interesting to have a close view of the mesh at the wall/fluid interface. Regards, 
Hi
I can not find IBM in OF1.6ext can you give me its position in application folder ? Regards 
Hey David,
it certainly looks very good, well done! Just a question, since you are dealing with a 2phase flow, can you confirm that the mass (VOF) is conserved with this implementation? 
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However, a little "liquid" is observed leaking from within the IB boundary (only happens when solid phase in gas phase) . The reason is that the constraint is applied onto the solid phase after UEqn and pEqn is solved. It means that during the sub timestepping (solving p and U), there is no CONSTRAINT on the solid phase. To avoid this problem the constraint might be applied in every sub timesteps, but it's computational expensive. If someone has good advice, please feel free contact me. 
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slides: Source codes of IB method in OF1.6ext Note that the IB method in OF1.6ext uses IBMask (0  inside IB boundary, 1  fluid domain) to calculate various fields (e.g. p. U), hence physical behaviour inside the immersed body is not solved. 
Greetings to all!
Thank you David for posting the direct links to those files! I've finally come around to git'ifying this source code and creating a wiki page for the Immersed Boundary toolkit:
Best regards, Bruno 
good job, wyldckat!
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Hi all,
I just wanted to ask if there has been any update in regard to implementation of IBM in official openFoam or at least in OpenFOAM 3.0ext. I am working with the one that has been implemented in OpemFOAM 1.6ext but I am not satisfied with the solver and stability of the solver at all. The solver terminates when bounding k, or omega warning appears. And, I realized that bounded schemes are not available in of1.6ext. Any comments would be greatly appreciated.  Moderator note: This topic is discussed further here: http://www.cfdonline.com/Forums/ope...m31ext.html 
Fictitious domain solver
Is the fictitious domain solver (mentioned below) available somewhere to test?
Thanks! Quote:

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Thanks David!

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