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Old   June 21, 2012, 02:57
Default Trailing edge mesh problem
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Hello everyone,

i am meshing an 2-D airfoil in a wind tunnel with y+=1 and unstructured mesh away from airfoil.i am facing problems while generating boundary layer mesh on the trailing edge of the airfoil. i am using wedge corner shape option here which gives me this ERROR: NODE XXXXX(increases whenever i choose this option eg 3342,3489,3571.... ) on the exterior boundary is merged. i will be very thankful if any other method is enlightened other than this method OR the correct way in approaching wedge corner option.

thanks in advance

bharat
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Old   June 21, 2012, 05:59
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may I see your decomposition in area of trailing edge?
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Old   June 21, 2012, 06:57
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Quote:
Originally Posted by -mAx- View Post
may I see your decomposition in area of trailing edge?
Hey Max,

thanks for your reply, here i post you the decomposition area for trailing edge
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Old   June 21, 2012, 07:02
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try to do one more split along x from trailing edge.
Then don't "close" the BL at trailing edge, but extend it along this split.
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Old   June 21, 2012, 08:38
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thanks for the suggestion but, i apologize for not mentioning this:- as i have to create unstructured mesh near the airfoil(inside the box only) and continue meshing with structured(quad/map) away from the box in the wind tunnel. as extending BL along that split will create meshing problems further. is there any other way out?
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Old   June 21, 2012, 08:45
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where should be the problem?
Can you send me your dbs file
PS: Why are you decomposing your domain around your airfoil, as you would mesh it with hexa? And finally you mesh it with tri?
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Old   June 22, 2012, 03:33
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ok since I cannot see what's going on the trailing edge, you may try to merge the domain with airfoil and the one behind the trailing edge.
Then split again axial from trailing edge and extend the BL here.
The wake will be finer meshed
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Old   June 22, 2012, 06:23
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i am unable get it. i would be thankful if any picture is provided.
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Old   June 22, 2012, 07:39
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Sans titre.jpg
Merge red square domain with blue one
One it is done, split the new domain, along the black dotted line
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Old   June 22, 2012, 09:37
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thanks for the image, since i am new in using BL for simulations, i have one doubt:- is it okay to elongate the BL throughout the stretch. because i'll be using some turbulence models like S-A and SST, does it effect my result?
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Old   June 25, 2012, 01:00
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Since you are no more at wall proximity, I don't think it could be a problem (that's my opinion).
By enabling aspect-Ration algorithm, you can enlarge the BL away from wall
Again all those stuffs could be preventing if you solve your trailing edge issue
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Old   June 30, 2012, 00:57
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Hey Max,

thanks a lot for your comments that helped me a lot . my problem is solved. i made it into blunt(trailing edge) which was much easier to mesh

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