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famerfamer June 8, 2011 15:52

mesh within certain angles
 
1 Attachment(s)
Hey guys,

How to deal with mesh in the sharp angle area as marked in the attached picture? The problem is that the room becomes narrower when it approaches the thinner corner.

The skewness angle there is very large. Is there any tool in the starccm I can use to solve this problem?

Thanks for any help!

daveatstyacht June 10, 2011 13:51

If your issue is specifically with a prism layer in that area, you can try changing the layer reduction percentage and minimum thickness percentage under the prism layer mesher options.

famerfamer June 10, 2011 15:21

Quote:

Originally Posted by daveatstyacht (Post 311518)
If your issue is specifically with a prism layer in that area, you can try changing the layer reduction percentage and minimum thickness percentage under the prism layer mesher options.

Thanks but what I'm concerning now is not the prism layer but the mesh in that area. Do you have any idea of how to deal with the sharp angles?

daveatstyacht June 11, 2011 07:03

Perhaps try refining either the surface or the volume cells using a volume control? You could also refine it and modify your geometry to eliminate the corner's point such that the if the modification is very minor it will have minimal impact on the resulting flow. I am not sure how important capturing the flow in the smaller end of the corner is to capturing your flow without knowing the details of what you are trying to capture.

rwryne June 11, 2011 10:27

Quote:

Originally Posted by daveatstyacht (Post 311576)
Perhaps try refining either the surface or the volume cells using a volume control? You could also refine it and modify your geometry to eliminate the corner's point such that the if the modification is very minor it will have minimal impact on the resulting flow. I am not sure how important capturing the flow in the smaller end of the corner is to capturing your flow without knowing the details of what you are trying to capture.

A good way to accomplish the above is to use the feature curve ont he corner to make a smaller surface mesh. Change your growth ratio so that the cells grow more slowly away from the small line source.

famerfamer June 15, 2011 15:29

Quote:

Originally Posted by rwryne (Post 311590)
A good way to accomplish the above is to use the feature curve ont he corner to make a smaller surface mesh. Change your growth ratio so that the cells grow more slowly away from the small line source.

Thanks. I'm interested in the feature curve way. Could you please explain more in detail about how to use it to control the surface mesh in that area? Thanks.

famerfamer June 15, 2011 15:31

Quote:

Originally Posted by daveatstyacht (Post 311576)
Perhaps try refining either the surface or the volume cells using a volume control? You could also refine it and modify your geometry to eliminate the corner's point such that the if the modification is very minor it will have minimal impact on the resulting flow. I am not sure how important capturing the flow in the smaller end of the corner is to capturing your flow without knowing the details of what you are trying to capture.

It's not the major part and I have no idea about its impact on the flow. What I know is it couldn't be converged when the skewness angle is around 132 degree. Currently it still has a 92 degree. But anyway, thanks for your reply.


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