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-   -   [ICEM] Blocking For Swept Wing (http://www.cfd-online.com/Forums/ansys-meshing/104491-blocking-swept-wing.html)

air_engineer_arsenal July 11, 2012 00:56

Blocking For Swept Wing
 
1 Attachment(s)
Hi All
I am new on this community and came here to get some help regarding the blocking for a Swept Wing. Previously I have visiting the community as a guest and got a lot of help regarding wing meshing for a simple rectangular wing in the thread "Structured Hexa Mesh on Wing". I found a nice discussion and different blocking strategies for a rectangular wing which actually helped in understanding new things in ICEM CFD. Now I have a problem in hand regarding the CFD analysis of a simple swept back wing. I need help for blocking the wing. I need to know how the blocking strategy in the above mentioned thread will change when we have a swept back wing or is there a method entirely different for this wing. I am attaching my .tin file in this post. Looking for some good help

Regards

Ralen July 11, 2012 02:40

Geometry file in attachment is empty.

air_engineer_arsenal July 12, 2012 00:13

1 Attachment(s)
Here are the .tin and .prj files

Regards

Far July 12, 2012 02:12

same blocking strategy will work fine.

air_engineer_arsenal July 12, 2012 11:06

Thanks Far for your reply. Can you please explain a bit how we will tackle the region in front of leading edge which is left empty(leading edge at root and tip is not aligned) by the swept wing as compared to rectangular wing and secondly the domain at the inlet is C-type but the blocking strategy explained for rectangular wing was with the rectangular type at inlet. so how to go about this? I am only confused in these two points, please help me clarify these. Thanks

Regards

diamondx July 12, 2012 11:52

About the C-Type geometry for the inlet, just initialize a block and do association according to the picture below, nothing really special. you will need to create an o-grid inside, and select face so the quality of your elements can be higher (see picture below number 2).
beside the ogrid, just perform you blocking as you are dealing with a rectangular shape. just try...

https://dl.dropbox.com/u/35161486/swept_wing_1.png


https://dl.dropbox.com/u/35161486/swept_wing_2.png

Far July 12, 2012 12:14

1 Attachment(s)
Or you can use the half o-grid (aka c-grid) and then another split at the trailing edge. And another split in ogrid to make the boundary layer meshing. I am attaching basic blocking and now your work is to associate inside edges to wing curves, and some working on blocks inside the tip region.

http://img16.imageshack.us/img16/8243/30161473.png

http://img9.imageshack.us/img9/2862/42400860.png

http://img441.imageshack.us/img441/882/13306422.png

air_engineer_arsenal July 13, 2012 09:58

Quote:

Originally Posted by Far (Post 371161)
Or you can use the half o-grid (aka c-grid) and then another split at the trailing edge. And another split in ogrid to make the boundary layer meshing. I am attaching basic blocking and now your work is to associate inside edges to wing curves, and some working on blocks inside the tip region.

http://img16.imageshack.us/img16/8243/30161473.png

http://img9.imageshack.us/img9/2862/42400860.png

http://img441.imageshack.us/img441/882/13306422.png

Thanks alot Far and Diamondx for your quick help. I have almost understood the procedure except few things. Far have you made vertical and horizontal splits in the main block before inserting C-grid or after the C-grid you made the slpits? and have you made the horizontal split in the main block above and below wing or its just the C-grid which I am considering the horizontal split?and last thing.... for inserting C-grid have you selected the face in front of leading edge or what else you did? Thnks

Regards

Far July 13, 2012 10:08

Quote:

Originally Posted by air_engineer_arsenal (Post 371320)
Thanks alot Far and Diamondx for your quick help. I have almost understood the procedure except few things. Far have you made vertical and horizontal splits in the main block before inserting C-grid or after the C-grid you made the slpits? and have you made the horizontal split in the main block above and below wing or its just the C-grid which I am considering the horizontal split?and last thing.... for inserting C-grid have you selected the face in front of leading edge or what else you did? Thnks

Regards

I did not make the horizontal spit al all. Vertical split is made after c-grid creation.
May be by horizontal split you mean the split on the edge in the z direction. It does not make any difference if you make it before c-grid or after it. But I prefer it after c-grid.
For C-grid I have selected three faces: 1) Symmetry 2) opposite to symmetry (side in above files) and outlet face.

air_engineer_arsenal July 17, 2012 03:22

Quote:

Originally Posted by Far (Post 371321)
I did not make the horizontal spit al all. Vertical split is made after c-grid creation.
May be by horizontal split you mean the split on the edge in the z direction. It does not make any difference if you make it before c-grid or after it. But I prefer it after c-grid.
For C-grid I have selected three faces: 1) Symmetry 2) opposite to symmetry (side in above files) and outlet face.

Thanks a lot Far for your continuous guidance. I have done all up till the steps you posted in your blocking files but still confused in some things. I am splitting the tip block vertically and inserted Y-block for trailing edge and Ogrid for leading edge blocks. All is fine up till here. Now I have to associate edges to curves of wing and for that I merged the vertices at trailing edge using collaspe block command...Is this the right way to move forward? Then after associations we have to adjust the blocking for better quality. In rectangular wing it was simple as the root and tip are aligned so we aligned vertices(in straight line) to get blocks but here root and tip of wing is not aligned rather tip is swept back....so my question is do we align vertices in straight line as were doing in rectangular wing case or we need to align it along the direction of wing sweep for better quality mesh? which option is good? if later option is good for adjusting blocks then how it will effect other blocks? Thanks

Regards

air_engineer_arsenal July 17, 2012 06:11

2 Attachment(s)
the fallowing figure shows the blocking adjustment about which I was talking about in the last post, red lines shows the direction in which I am adjusting the tip block...is it right? and my effort's .blk and .prj file is also attached.

Far July 24, 2012 02:38

I got the duplicate blocks from files you have just uploaded.

air_engineer_arsenal July 24, 2012 11:21

Quote:

Originally Posted by Far (Post 373139)
I got the duplicate blocks from files you have just uploaded.

sorry didnt get your point Far?
I am just asking about the direction in which blocking will be adjusted and also about the block split behind the trailing edge? Thanks

Regards

Far July 24, 2012 11:52

1 Attachment(s)
Your blocking adjustment is good enough. There were some duplicate blocks at the outlet and just deleted them. Also made some minor adjustments on vertices

blocking, tin and prj are attached

http://img838.imageshack.us/img838/9472/13277840.png


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