[kev4573]

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,

Kevin

[marine]

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]

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]

Hi,
there is a program called Icon FOAMpro which handles snappyhexmesh in a comfortable way for the customers of of Icon http://www.iconcfd.com/.
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 http://www.opensourcecfd.com/confere...oceedings.html

http://www.opensourcecfd.com/confere...2009_Islam.pdf 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 http://engits.eu/cms/index.php?id=5
but I am not sure.

elvis

[stawrogin]

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

stawrogin