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fat bug December 3, 2007 14:41

inflation area with steps
 
Several small steps are included in flow axial direction due to diameter change.

I'm having a hard time adding inflation layers to these features.

To me, all these steps will cause local turbulence. Therefore, I'd like to inflate this area to get more accurate results. The mesher will freeze at "surface mesh" level. I'm going nowhere on this.

I'd appreciate any help!


Glenn Horrocks December 3, 2007 17:39

Re: inflation area with steps
 
Hi,

If you want to resolve the turbulence generation caused by little steps then you will need a very fine mesh in the area to fully resolve the flow in this area. If you do this you will then have a fine surface mesh to resolve the steps.

My guess is you are trying to put too large a mesh on the steps and that is why it is having problems generating the mesh.

Glenn Horrocks

fat bug December 4, 2007 09:08

Re: inflation area with steps
 
I did run a Geometry check and set the surface mesh size smaller then 1/5 the min sliver or edge length.

Without inflation, all the other meshing setup will work fine on this model. It will only stall when I add inflation layers.

I did try refining the mesh, it worked, however, the mesh file was huge.

Would I be able to refine the mesh locally and do a "fast" transition to minimize the file size?

Thanks!

CycLone December 4, 2007 10:29

Re: inflation area with steps
 
You can do this, but you'll lose all the detail of the flow through your "fast" transition. If this level of detail is indeed necessary, you'll need to have a very large mesh.

You might be able to slice your geometry into sweepable regions and use the sweep method on these instead (assuming you are using the Workbench Meshing App). Alternatively, use a structured meshing tool like ICEM CFD Hexa to craft a hex mesh that resolves your details more efficiently.

-CycLone


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