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-   -   can i have two blockmesh blocks one inside each other (

mihaipruna April 7, 2012 08:20

can i have two blockmesh blocks one inside each other
i'm finding difficult to capture geometry such as a thin wing for SHM without creating a huge number of cells which crashes SHM.
i want to intersect the STL with the minimum amount of cells and for that i want to create a finer block around the STl and a coarser block around it.
Can I do that with only two blocks, one inside each other?

lovecraft22 April 7, 2012 08:54

I would probably do that in snappyHexMesh rather than in blockMesh.

mihaipruna April 7, 2012 09:20

I have a refinement box defined in SHM

but the stl has to intersect the blocks in blockmesh otherwise it doesn't get captured, right?
so a thin wing, even if it intersects spanwise and chordwise, if it doesn't intersect thicknesswise it won't show up?

lovecraft22 April 7, 2012 13:18

Sorry, I haven't quite understood what you mean… Do you want to refine the mesh on the domain or on the surface of your geometry?

mihaipruna April 7, 2012 14:55

what i want is to use blockmesh to make a finer block where the object is to ensure intersection and a coarser block for the whole domain. ideally with just two blocks.

lovecraft22 April 7, 2012 15:05

1 Attachment(s)
So you need something like what depicted in the attached image.

The domain is a simple square block from blockMesh.

The refinement zones are two blocks from SHM.

mihaipruna April 7, 2012 15:40

but what if you replace the sphere with an airfoil whose thickness is less than the height of a BM block?

lovecraft22 April 8, 2012 04:58

mmm… could you post a picture that shows your blockmesh and your airfoil within it?

mihaipruna April 8, 2012 09:03

thanks lore. i think my mesh is pretty coarse actually. i'll try another approach for airfoils, namely a fine 2d mesh with further refinement around the surface. that should give me the resolution i need without the resource drain.

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