makeAxialMesh.md

makeAxialMesh

Reference:

1. cfd-china thread
2. A Japanese blog
3. OpenFOAM wiki
4. Jianshu blog

Source code

Download makeAxialMesh for OpenFOAM 2.x versions from here.
Compile:

./Allwmake

How to use

1. Create a 2D axisymmetric mesh using ICEM

Make sure the axis is set in the boundary conditions.

2. Convert ICEM 2d mesh to OpenFOAM

Use fluentMeshToFoam:

fluentMeshToFoam fluent.msh

Note: Don't use scale option! Use mm to prevent roundOff error.

3. Convet the mesh type

Use makeAxialMesh:

makeAxialMesh -axis AXIS -wedge frontAndBackPlanes -offset 1e-6 -overwrite
# Use flattenMesh to prevent checkMesh error
flattenMesh

Please note! The config -offset 1e-6 is used to fix this error report:

Changing patch types 
 Changing AXIS to symmetryPlane
 Changing frontAndBackPlanes_pos to wedge
 Changing frontAndBackPlanes_neg to wedge



--> FOAM FATAL ERROR: 
Symmetry plane 'AXIS' is not planar.
At local face at (-0.04525201889605017 0 0) the normal (0 -1 0) differs from the average normal (0 -0.4972222222222222 0) by 0.2527854938271605
Either split the patch into planar parts or use the symmetry patch type

    From function symmetryPlanePolyPatch::n()
    in file meshes/polyMesh/polyPatches/constraint/symmetryPlane/symmetryPlanePolyPatch.C at line 64.

FOAM exiting

4. Collapse mesh

Create collapseDict file in system folder:

FoamFile
{
    version         2.0;
    format          ascii;
    class           dictionary;
    location        "system";
    object          collapseDict;
}

collapseEdgesCoeffs
{
    minimumEdgeLength   1e-6;

    maximumMergeAngle   179.5;
}

Run this command:

collapseEdges -overwrite
# Scale mesh from mm to m
transformPoints -scale "(1e-3 1e-3 1e-3)"

See Ref[2] for more information.

5. Check

Check mesh and boundary patch names in constant/polyMesh/boundary.

checkMesh