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-   -   How to create Prism Layer in OpenFOAM? (http://www.cfd-online.com/Forums/openfoam/91585-how-create-prism-layer-openfoam.html)

j-avdeev August 16, 2011 07:01

How to create Prism Layer in OpenFOAM?
 
Does OpenFOAM have something for creating prism layer as Star-CCM+ has?

jango August 16, 2011 09:14

Boundary layer in OpenFOAM
 
1 Attachment(s)
Hello j-avdeev,

with blockmesh you can create graded mesh blocks (according to chpt. 2.1.6. in Users guide). If you want to create a boundary layer, it may be useful to divide up the blocks in graded and non graded cells according to the attached example.

greets,

Jan

j-avdeev September 19, 2011 04:50

Thanks, Jan.
Can you also describe how you made this blockMeshDict?
Too much vertices - what additional software you use?

jango September 19, 2011 06:27

Prism layers in openFOAM
 
1 Attachment(s)
Hi j-avdeev,

This model (see attached files) I created with a python script. With python you can do parametric modelling and it`s much easier than editing the blockMeshDict by hand. For 3D- boundary layer you can use salome (www.salome-platform.org)

greets,

Jan

j-avdeev September 23, 2011 16:38

Also connected theoretical question -
how you choose sufficient count of boundary layers?
and mesh frequency?

Are you just use Courant number (as written in User Guide) or something else?

jango September 25, 2011 05:43

Quote:

Originally Posted by j-avdeev (Post 325415)
Also connected theoretical question -
how you choose sufficient count of boundary layers?
and mesh frequency?

Are you just use Courant number (as written in User Guide) or something else?

Hi j-avdeev,

that strongly depends on your desired results. In the theorical way you can do it as written in UG. In practical experience it`s mostly the case, that you approximately estimate the number of cells without boundary layer and set up a model with a coarse mesh in a parametric way. Making sure, the model works, you simply change the parameters for mesh refinement and boundary layers.
If you`re not interested in near wall results at some parts of the model and you don`t have heated walls or something, you can simply calculate the model without boundary layers at this regions.

have fun trying it and a nice weekend,

Jan


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