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-   -   Using snappyHexMesh to fill cells within predefined boundary (

kev4573 April 9, 2010 09:28

Using snappyHexMesh to fill cells within predefined boundary
Does snappyHexMesh require a background mesh to work? What I'd like to do is predefine all my boundaries (farfield and body-fitted), and then let snappy fill in the cells. As I understand it, snappy lets you import a geometry file (*.stl), but you must place it in a preexisting mesh.

Best regards,


marine April 19, 2010 08:49

First you have to mesh the domain around your surface with blockMesh and then with the snappyHexMEsh you can choose to keep the external or internal field of your geometry.

kev4573 April 20, 2010 15:55

Okay I guess that answers my question then. I don't know exactly how the snappy algorithm works, but I wonder if it's capability could be extended to total automatic meshing, given all boundary meshes (body and far-field).

elvis April 21, 2010 04:03

there is a program called Icon FOAMpro which handles snappyhexmesh in a comfortable way for the customers of of Icon
It is not part of OpenFoam but a seperate product.

Some of the customers are Audi,Volkswagen, Seat and Bombadier.
In an presentation given at OSCIC2009 Slides 21,22,25,29
you will see that snappyhex mesh is the base for Meshing but that some additional features like cell quality optimisation are added by icon.

A perfectly tweaked "dictonary" for snappyhex mesh is important, as automatik meshing of a windtunnel simulation with 47 Mio cells takes them 2,5 hours on a 193 cpu core computer.

If I am not mistaken snappyhex has been used for farfield mesh
but I am not sure.


stawrogin May 21, 2010 04:09

Hi Elvis,
looks quite interesting.
Did you ask icon for their snappy-adaptation? Snappy is a part of an opensource system. If icon's snappy is based on OpenCFD's snappy it is opensource as well. They have to provide it to everybody, I think if they give it to their customers.

Best regards


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