[comingdaytime]

Dear All,

I pretty new with snappyHexMesh. I just finish the central part refinement of the cyclone, which is attached here.

But does anyone know how should I add inflation layers to it?
I used this in snappyHexMeshDIct, but it is not working:

addLayers true;
......

// Settings for the layer addition.
addLayersControls
{
// Are the thickness parameters below relative to the undistorted
// size of the refined cell outside layer (true) or absolute sizes (false).
relativeSizes true;

// Per final patch (so not geometry!) the layer information
layers
{
cyclone.stl_walls
{
nSurfaceLayers 3;
}
}

// Expansion factor for layer mesh
expansionRatio 1.1;

// Wanted thickness of final added cell layer. If multiple layers
// is the
// thickness of the layer furthest away from the wall.
// Relative to undistorted size of cell outside layer.
// is the thickness of the layer furthest away from the wall.
// See relativeSizes parameter.
finalLayerThickness 0.5;

// Minimum thickness of cell layer. If for any reason layer
// cannot be above minThickness do not add layer.
// Relative to undistorted size of cell outside layer.
minThickness 0.1;

// If points get not extruded do nGrow layers of connected faces that are
// also not grown. This helps convergence of the layer addition process
// close to features.
// Note: changed(corrected) w.r.t 17x! (didn't do anything in 17x)
nGrow 1;

// Advanced settings

// When not to extrude surface. 0 is flat surface, 90 is when two faces
// are perpendicular
featureAngle 60;

// At non-patched sides allow mesh to slip if extrusion direction makes
// angle larger than slipFeatureAngle.
slipFeatureAngle 30;

// Maximum number of snapping relaxation iterations. Should stop
// before upon reaching a correct mesh.
nRelaxIter 5;

// Number of smoothing iterations of surface normals
nSmoothSurfaceNormals 1;

// Number of smoothing iterations of interior mesh movement direction
nSmoothNormals 3;

// Smooth layer thickness over surface patches
nSmoothThickness 10;

// Stop layer growth on highly warped cells
maxFaceThicknessRatio 0.5;

// Reduce layer growth where ratio thickness to medial
// distance is large
maxThicknessToMedialRatio 0.3;

// Angle used to pick up medial axis points
// Note: changed(corrected) w.r.t 17x! 90 degrees corresponds to 130 in 17x.
minMedianAxisAngle 90;


// Create buffer region for new layer terminations
nBufferCellsNoExtrude 0;


// Overall max number of layer addition iterations. The mesher will exit
// if it reaches this number of iterations; possibly with an illegal
// mesh.
nLayerIter 50;
}



Thank you
Best Regards

Litchy

[KateEisenhower]

Hello,

inflation layers are boundary layers, right? What is the error message you get?

Best regards,

Kate

[comingdaytime]

Originally Posted by KateEisenhower

Hello,

inflation layers are boundary layers, right? What is the error message you get?

Best regards,

Kate

Hallo, Kate,

Yes, inflation layer is boundary layer. There is no error message, simply no inflation layer created, just like the step 2 (snapping).

Right now I get the inflation layers somehow, I guess I was not setting the inflation part correctly, so It did not recognize it.

Thank you for your reply

Best Rrgards

Litchy

[mwaqas]

Hi Litchy,


I know, it is an old thread but may be useful for someone else.

I think, the problem with you patch name


layers
{
cyclone.stl_walls
{
nSurfaceLayers 3;
}
}




"cyclone.stl_walls", it should be you patch name, instead of .stl file name


Regards