[shantanukale]

Hello!
What should be the file format for .eMesh file (binary or ascii)?
Also, I can see the geometry after running snappyHexMesh.
The geometry I am trying to simulate is circular cylinder in a rectangular domain.

Thank you.

[cutter]

Hi,

it's a simple ASCII file format. Have a look at the tutorial cases! You can visualize the *.eMesh files using Paraview/ paraFoam.

Cutter

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  2.2.x                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       featureEdgeMesh;
    location    "constant/triSurface";
    object      Sample.eMesh;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //


// points:

2229
(
(2.6 7.44 3.8)
(2.6 7.44 0)
(1.95 7.44 3.8)
...
(0.419528 0.45 2.81578)
(0.425194 0.45 1.63303)
)


// edges:

2233
(
(171 172)
(173 174)
(175 173)
...
(369 25)
(26 370)
)

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //


// ************************************************************************* //

[shantanukale]

Thanks a lot...
The file that i have generated using surfaceFeatureExtract shows binary format.
i cant see the co-ordinates of the points.
in this case, what best can be done?

Thank You.

[cutter]

Make sure the option writeFormat is set to ascii in you ./system/controlDict.

You may also set the option writeObj to yes in the file ./system/surfaceFeatureExtractDict. This will write *.obj files to ./constant/triSurface. These files are also human readable and can be visualized using Paraview/ paraFoam.

Cutter

[shantanukale]

Thanks a lot...
The file is now written in ascii format.
How to remove cells in between a geometry. i am trying to mesh circular cylinder in square domain.

Thank You.

[cutter]

You need to specify a point within your fluid domain in order the tell snappyHexMesh whether it needs to mesh at the inside or outside of your cylinder. This is done with the option locationInMesh in the ./system/snappyHexMeshDict.

Have a look at the tutorial cases (motorBike for example) and the documentation:

http://www.openfoam.org/docs/user/snappyHexMesh.php
https://sites.google.com/site/snappy...ppyhexmeshdict

Good luck!

Cutter

[shantanukale]

Thanks a lot...
my domain size is (0,0,0) to (40, 20, 0.1)
i have the cylinder generated in paraview and then translated it using translation feature so that it can fit in the domain.
the location of the cylinder in the domain is (10.5,10.5,0.05)
locationinmesh point co-ordinates are (8.009512, 8.00900512, 0.019009512)

Thank You..

[cutter]

No problem, nice to hear it's finally working.

Now it's my turn to ask questions: What are the steps to export the cylinder surface from Paraview? I tried it myself, the resulting STL file (via File->Save Data) is missing lots of triangles.

Thanks and good luck with your case!

Cutter

[shantanukale]

The steps that I have followed are:
1. Generate a cylinder using sources option in menu bar
2. Using features, transform the geometry to the desired location (we may have to use the base geometry for this purpose, say a box in which the cylinder is located.
3. Then extract surface keeping the translation active.

Thank You.

[nacholarrabide]

hi all,

sorry if this is not the right post for this question. If so, please point me in the right direction.

I'm trying to generate edges for a tube-like geometry using the surfaceFeatureExtract utility from foam-ext 3.2. I can get the right edges, but in .obj format and not .eMesh format. The thing is that I cannot input these to snappyMeshHex for edge snapping. Which is the right way to do this in foam-ext 3.2?

Thanks in advance,

Nacho

[nacholarrabide]

Well, I found a way out. Apparently the version of OpenFOAM behind foam_extend 3.2 is older than 2.2, so the new features of surfaceExtractFeatures (like using a Dict file) are not there. yet. My workaround was to install OpenFOAM 3.0 (sudo apt-get install openfoam30) and in a separate shell use the new utilities to preprocess the mesh. This is far from clean, but it works out well, since the new and old OpenFOAM mesh file formats are compatible (so far).

Nacho