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pendyala August 7, 2013 00:17

Boundary layer on Unstructured mesh
Hello All, I have a small question. Could we create a boundary layer on 3d unstrured mesh in gambit. I need to capture flow seperation and since, I cannot have a really fine mesh on my object, I wanted to use BL. This doesn't work. So any suggestions??

Thanks in advance.

-mAx- August 7, 2013 05:57

sure you can:

pendyala August 7, 2013 09:53

The boundary layer is placed inside the body. Like on the surface, but can't it grow above the 3d structure? For ex in the sail boat meshing in gambit tutorial 14. I hope u got my question.

-mAx- August 7, 2013 10:34

in 3d the BL has to be attaches to the wall surface
Else post pictures

pendyala August 7, 2013 11:29

In the picture I uploaded to see the flow desperation I have to refine my mesh and since I cannot mesh so fine due to system limitations I have to have boundary layer. But when Put a boundary layer, I couldn't have it properly.

-mAx- August 7, 2013 11:38

display how look your BL like, even if you cannot create it.

pendyala August 7, 2013 11:59

1 Attachment(s)
I am currently out of my workspace. So cannot publish pictures right now. Will do shortly. In the image I updated its the front part of my body. If u observe there is higher space between each cell. So to decrease cell distance I want to lay a BL. How to attach a BL to this surface?? Do we go SELECT BL give the first length. If I do so, the BL grows on the surface of face . But it doesn't grown on top of face( grows exactly the way it is shown in link u posted). My basic is how to reduce the distance between cells without effecting

pendyala August 7, 2013 20:13

I want boundary layer in the edges in the 1 st block but I'm getting as in the picture..

pendyala August 7, 2013 20:23

Below image, as u see, in the 5 boxes box like faces available, I want to have BL on each face with spacing .00001 intial length. So, I couldn't ge that though. The while patch is the BL I'm getting. So, any suggesting as to how that works??

-mAx- August 12, 2013 00:41

in your picture I don't see any BL attached.
If you do it right, you select the surfaces of your body as attachment, and give first cell's height and also how many layers you want.

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