ShinyRiver,

Any motion will be described by the solidBodyMotionFunctions-class. This is the same as one usually uses for moving meshes.
If you have the desire to add an additional function you can do that by copying an existing function e.g. translation and modify it as you please. After you did that, add the path into the files (Make folder) and compile the entire class. However it's not the best solution since you're changing the source code however it works.

Best wishes
Daniel

Make immersed boundarys compressible
 

Hello everybody,
I am using ImmersedBounderys in foamExtend-3.2 and I want to adapt the compressible rhoPisoFoam-Solver to calculate use ImmersedBoundaries.
So far, I changed the "immersedBoundaryAdjustPhi.H" from "fvc :: makeRelative (phi, U);" to "fvc :: makeRelative (phi, rho, U);"

Using rhoPisoFoam as a basement, I've set up the solver as the solver_coockbook suggested.

But every time I try to run it, an error occurs, caused by a division by zero.

Responsible is basically cellIbMaskExt at 0 positions (solid body). The values for rho, h ans psi are at the same position also 0.
Unfortunately, rho and h are poor implemented. So that correctBoundaryConditions() does not help at all.

I hope someone can help me to make the solver run.

I read, that the used implementation of immersedBoundaries, are of "Discrete Forcing Approach" and uses "direct imposition of boundary conditions". Are there more infomations about the used algorithm?

Regards
RobertG

Hi all,

I am using foam-extend 4.0 and currently trying to run the tutorial movingCylinderInChannelIco. The case seems to run, but as soon as I want to display the results in paraFoam I get this error:



size of field refValue (96) is not the same size as the patch (0)
on patch ibCylinder of field U in file "/home/username/foam/foam-extend-4.0/tutorials/immersedBoundary/movingCylinderInChannelIco/0.2/U"


By inspecting the velocity files, in 0/U the refValue is defined as uniform, while in 0.2/U refvalue becomes nonUniform and defined with a List of vectors. Is the error related to this difference? How can I fix it? Is it a paraFoam issue or there is something wrong with the case? I did set up a simple case very similar to this tutorial, and modified the U file (e.g. by specifying a nonUniform List also in 0/U) but the error is the same.



Thank you in advance for your feedback
A.

foam-extend-4.0/4.1 tutorial blockMesh
 

Dear Foamers,

I am running a bunch of the Immersed Boundary method tutorials, specifically the movingCylinderInChannelIco tut. I played around extensively and a lot of stuff works quite well but I cannot refine the blockmesh. When changing the mesh in the blockmeshdict the solvers and particularly the meshInitialisation complain. I attached the error below. It's seems to be the same for both 4.0 and 4.1. Can someone help with it?

Thanks in advance,
Cheers
Max

ERROR:


Create dynamic mesh for time = 0

Selecting dynamicFvMesh immersedBoundarySolidBodyMotionFvMesh


--> FOAM FATAL ERROR:
Error in point ordering: mixed used and unused points at the end of point list.
Last used point: 0 (-1 -0.5 -0.04)
First unused point: 1 (-0.982857 -0.5 -0.04)
and point 1 (-0.982857 -0.5 -0.04) is used by a live face.
Face 0 4(1 177 22353 22177) with points 4((-0.982857 -0.5 -0.04) (-0.982857 -0.492 -0.04) (-0.982857 -0.492 0.04) (-0.982857 -0.5 0.04))
Done.

From function void polyMesh::initMesh()
in file meshes/polyMesh/polyMeshInitMesh.C at line 166.

FOAM aborting

@mfrz

Did you find anything on your problem. I am getting same thing in Foam Extend 4.1 as i am changing the mesh

Regards

This usually happens when you change the mesh but you forget to change the save/boundary file. Every time you change the mesh, you should copy the newly created boundary file and add the immersed boundary patch to it. You also have to change the StartFace value to the startFace value of the first patch. Take a look at the boundary file in save/ directory and prepare your boundary file accordingly after blockMesh.
After preparing the boundary file, don't forget to copy it to the save/ directory.