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Trouble with sharp trailing edge

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Old   August 10, 2011, 21:09
Default Trouble with sharp trailing edge
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Prakash Paudel
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I am meshing a wing in ICEM CFD. I want to start with meshing the surface. But, I cant seem to make the surface mesh smooth at the trailing edge. The edge looks like a saw tooth (Please see image). Anyone has any suggestions??

I am using all tri, patch independent shell meshing with the following values:

Root chord length: 1
Max element size for the Wing (in part mesh setup): 0.05
Global element Scale factor:1
Global element Seed size, Max element:5
Curvature/Proximity Based Refinement: Enabled with Min size limit: 0.00001
Elements in gap:1
Refinement:50
Ignore Wall Thickness: Disabled
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File Type: jpg saw-toothTrailing-edge.jpg (68.3 KB, 53 views)

Last edited by Prakash.Paudel; August 11, 2011 at 01:03.
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Old   August 11, 2011, 00:06
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Prakash Paudel
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Fewthings that i found would help eliminate my trouble,

1. Thin cuts:

I believe i cannot use thin cuts here unless i have an extra surface that extends from the trailing edge for the wake region or i use "create part" for trailing edge curve. All the points, curves and surfaces were named as "WING" since the creation of geometry using formatted point data.

2. Curve mesh setup:

I tried using curve mesh setup using the max size of 0.005 but the surface mesh still does not conform to the trailing edge. May be because my trailing edge is very sharp? I am using super-critical airfoil with ridiculously sharp trailing edge.

3. Edge criterion:

To use Edge criterion, I must mesh the fluid region first, delete the all volume mesh, and use Delauney.


Please correct me if anything. Any suggestion is appreciated.. Thanks

Last edited by Prakash.Paudel; August 11, 2011 at 01:47.
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Old   August 11, 2011, 15:42
Default Repair Geometry
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Prakash Paudel
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I realized that i have two curves each on leading edge and trailing edge because i made lofted surface for both top surface and bottom surface of wing. Is it a good idea to delete one curve each from both leading and trailing edge? Or is there a better way to deal with this geometry problem ??
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Old   August 12, 2011, 03:36
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Zhang Yang
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1: first thing to check is that is there a line between the upper und lower surfaces of the blade? If not, create it.

2: Thin Cut

3: Edeg Criterion
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Old   August 12, 2011, 14:01
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Prakash Paudel
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I have decided that I have to make my wing surfaces watertight in order to use octree mesh ( only octree mesh allows me to use thin cuts ). Build topology is the best option but I dont understand how it works. Anyone who has used build topology has any suggestions ???
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