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Old   May 15, 2007, 06:29
Default Hi there, I managed to set
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Thomas Jung
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Hi there,

I managed to set up a moving (i.e. shrinking) mesh, and calculate some diffusion on it, seems to work fine.
Now I would like to use the layer addition/removal stuff. Have been searching a lot on forum and wiki - but have to admit I could not get an idea how to use mesh modifiers. Also, there seems not to be any tutorial really using layer removal.

What I tried:
added this to my dynamicFvMeshDict:

bottom
{
type layerAdditionRemoval;
faceZoneName bottomFaces;
minLayerThickness 5e-3;
maxLayerThickness 1e-2;
oldLayerThickness -1;
active on;
}


where bottom is a patch adjacent to which I would like to remove layers.

Apart from this, I am just calling mesh.upgrade() in my application.
However, somethings missing - nothing happens
(well, the mesh moves as before and as expected, but no layers are removed...)

Maybe I somehow have to create that facezone - but have no idea how...
Any hints?

Thank you!

Thomas
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Old   May 18, 2007, 04:27
Default o.k. .... found and compiled t
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Thomas Jung
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o.k. .... found and compiled the utility "setSet", and can construct faceSets now. However I am in doubt if a faceSet is the same as a faceZone ... could someone help me, please?

Thanks!

Thomas
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Old   February 9, 2009, 06:09
Default Hallo Thomas i am at the sa
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patrick riemer
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Hallo Thomas

i am at the same point right now. I have a moving mesh with an oscillating plate. This patch is a wall, called plate. My mesh is deforming too much, so i need layer addition/removal.

It's important for me to solve that problem soon because i have to finish a thesis work.

I would be very thankful for some help.
I use 1.4.1-dev

- Do i need a file called meshModifiers in /constant? How do i introduce such faces rightExtrusionFace and leftExtrusionFace? What are they for?

- In the dynamicMeshDict:
How do i recompile movingConeTopoFvMesh.C for the case that i need another motion.
Desired function: u = dx/dt = VelAmplitude * cos(2*pi*freq*t) = VelAmp * cos(pi*t/VelPeriod)
In movingConeTopoFvMesh.C:
VelAmplitude * sin(t*pi/VelPeriod)
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Old   February 20, 2009, 06:36
Default Hello, I would need the same
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Virginie Ehrlacher
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Hello,
I would need the same kind of advice: how do we use the meshModifiers? I have added a meshModifier file in constant/polymesh, however teh solver does not seem to take it into account.
Do I need another line of code to have it understand that I want the meshmodifier to be used?

I am using the last version of OpenFOAM-1.5-dev (on svn) and I am working with the solver InterTrackFoam to simulate the flow of a viscous liquid over a slope.

Thank you in advance.

Virginie
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Old   February 20, 2009, 07:24
Default You will need to write your ow
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Hrvoje Jasak
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You will need to write your own topoChangerFvMesh class, which will incorporate mesh motion and mesh modifiers. There's plenty of examples in the library.

Hrv
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Old   March 31, 2010, 05:22
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Wolfgang W.
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Hello to you all,

I was wondering if one of you has had success in implementing a new topoChangerFvMesh class - especially with regard to merging layerAdditionRemoval and dynamic mesh motion.
I'm working on a problem which seems to resemble the one Patrick described very closely - I just use an expanding circular membrane instead of a plate.

I'm playing around with the movingConeTopoFvMesh class at the moment, trying to figure out how I can adapt it to my problem. Still, I fear that for a recently started OpenFOAM rookie it might be difficult to fight through all this without advice - especially with regard to including the mesh motion as well.

I would very much appreciate if anyone could point me to helpful examples of similar topoChangerFvMesh classes, provide some code fragments or any other advice.

Best regards,
Wolfgang
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