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Old   May 3, 2013, 01:29
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Paritosh Vasava
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I can not share the CAD model as it belongs to some company. But here are SHM and files that I used to generate mesh.

Meanwhile I'll prepare another CAD model that I can share and come back here.
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File Type: txt snappyHexMeshDict1.txt (2.6 KB, 1 views)
File Type: txt snappyHexMeshDict2.txt (2.6 KB, 0 views)
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Old   May 3, 2013, 01:43
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Andreas Wendy
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Quote:
Originally Posted by vasava View Post
I can not share the CAD model as it belongs to some company. But here are SHM and files that I used to generate mesh.

Meanwhile I'll prepare another CAD model that I can share and come back here.
maybe it iis best if you just create a dummy STl-file and upload the case with this geometry.

andy
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Old   May 3, 2013, 03:20
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Paritosh Vasava
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Meanwhile can you explain how AMI is generated?
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Old   May 3, 2013, 03:33
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Quote:
Originally Posted by vasava View Post
Meanwhile can you explain how AMI is generated?
Hi,

I normally work with OpenFOAM 1.6 extend with the integrated GGI.
But the AMI should be more or less the same.

1. Create two seperate meshes.
a) one for the static mesh
b) one for the rotating mesh

2. Merge both meshes with "mergeMeshes".
a) create a copy of one mesh and merge this copy with the other mesh
mergeMeshes copiedCase otherCase

3. modify the boundary file of the merged mesh
a) got to the merged case -> cobnstant -> polymesh. open the file boundary in a text editor
b) have a look at the patches wich are the base of your AMI
c) change first patch (e.g. AM1)

AMI1
{
type cyclicAMI; <- change type
nFaces 22416; <- use here original data from boundary file
startFace 1733766; <- use here original data from boundary file
matchTolerance 0.0001;
neighbourPatch AMI2; <- use name of patch from other mesh
transform noOrdering;
}

d) do same procedure to the second ami-patch just with the other patch names.


save the file and try to run the calculation with "pimpleDyMFoam"

best wishes

Andy
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Old   May 3, 2013, 06:03
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Paritosh Vasava
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Thanks. I am trying it now. Hope it works.
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Old   May 6, 2013, 06:03
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Quote:
Originally Posted by A.Wendy View Post
Hi,
1. Create two seperate meshes.
a) one for the static mesh
b) one for the rotating mesh
When I create the mesh with stl files, the process creates two folders 0.1 and 0.2. I assume 0.2 has the latest mesh and then copy it to the constant folder (and then do merging). Is this correct?

The second question: The merging operation seems to work fine but when I check the merged mesh the cellZones, faceZones and pointZones files are empty. What do you think is going wrong?
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Old   May 6, 2013, 06:07
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Quote:
Originally Posted by vasava View Post
When I create the mesh with stl files, the process creates two folders 0.1 and 0.2. I assume 0.2 has the latest mesh and then copy it to the constant folder (and then do merging). Is this correct?

The second question: The merging operation seems to work fine but when I check the merged mesh the cellZones, faceZones and pointZones files are empty. What do you think is going wrong?
you can use for snappy HExMesh the following line to write the mesh to the 0-folder/constant-folder

snappyHexMesh -overwrite


the zoning should be done after mergeing the meshes i think
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Old   May 6, 2013, 08:11
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Paritosh Vasava
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Well I tried the '-overwrite' but the problem of empty files still persists.

By the way how do you make your stl file? Do you export it as one surface or export it as one file containing several surfaces (inlet, outlet, wall etc)?

I will post this in the main forum as well.
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Old   May 7, 2013, 02:34
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Paritosh Vasava
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Here is link to the case files. The case is minimal so you have to start from scratch. Sorry about that but the files were too big.

http://www.mediafire.com/?y9i5lj4b1xxw3cr

Please let me know if you need something.

I am working with the propeller example to see if I can find some hints.
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Old   May 7, 2013, 04:22
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Quote:
Originally Posted by vasava View Post
Here is link to the case files. The case is minimal so you have to start from scratch. Sorry about that but the files were too big.

http://www.mediafire.com/?y9i5lj4b1xxw3cr

Please let me know if you need something.

I am working with the propeller example to see if I can find some hints.
I am working on it.
but my Computer has only few ressources left so it will take some time...

andy
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Old   May 7, 2013, 04:31
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Paritosh Vasava
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I appreciate your help. I am now following the propeller example where use of multiple stl files and AMI is demonstrated.

Thanks again.
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Old   May 7, 2013, 07:35
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hi,

i just had a look at your case.
your setup of geometry will not work this way. your sliding patch have to be of a cylindrical shape. but yours is not. even i would change the snappy hex mesh entries.
i think it would be more easy to have a geometry of the rotating part of your mixer not of the fluid.
the axis of your mixer is also moving so i would put it into the moving domain too.

if the tank is cylindrical you may not need to create with a stl file. you can use blockMesh and snappy Hexmesh only.
can you upload a stl/obj. file of the mixer only?

andy
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Old   May 7, 2013, 08:00
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Paritosh Vasava
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Here is link to the impeller and mixer files.

http://www.mediafire.com/?g5bb7tqlq1bubnp

Thanks!!
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Old   May 7, 2013, 08:18
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hi,

i need the geometrie of the tank and blades not of the computational area.
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Old   May 8, 2013, 02:31
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Paritosh Vasava
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Here is the link to those files. http://www.mediafire.com/?xmzqjhcu354go3r
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Old   May 8, 2013, 08:58
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Quote:
Originally Posted by vasava View Post
Here is the link to those files. http://www.mediafire.com/?xmzqjhcu354go3r
Hi

here you find the "cleaned" case. just run the Allrun file. The boundary ist changed by hand maybe you can automatize it.

if you have quest just send a massage

http://ubuntuone.com/3ZKPM8nv9xDgZaSkhsVcoO

best wishes

andy
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Old   May 10, 2013, 03:17
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Paritosh Vasava
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I will check the case soon. Thank you very much for the help. I will get back if I am stuck somewhere.
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