CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > ANSYS Meshing & Geometry

[GAMBIT] Split edges?

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   February 20, 2010, 04:57
Default Split edges?
  #1
Member
 
smith
Join Date: Apr 2009
Posts: 75
Rep Power: 17
Zweeper is on a distinguished road
hey,

I'm trying to import some airfoil geometries from pro-engineer as ICES file format and it works good so far.

my problem is that i have just two edges which form the whole wing and therefore i can't create a smooth boundary layer around this airfoil.

I thought now maybe i can solve this problem by splitting my two edges into XX edges. I found a option where i can enter some coordinate values to split edges, but i asked my self if there is also an option to divide the edges with a ratio?

For example: i select 2 edges and i want to split each of them into XX new edges.


I hope you can help me with this.


Regards,
Zweeper
Zweeper is offline   Reply With Quote

Old   February 21, 2010, 10:47
Default
  #2
Member
 
smith
Join Date: Apr 2009
Posts: 75
Rep Power: 17
Zweeper is on a distinguished road
has nobody a clue about that problem?
Zweeper is offline   Reply With Quote

Old   February 22, 2010, 01:57
Default
  #3
Super Moderator
 
-mAx-'s Avatar
 
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41
-mAx- will become famous soon enough
Sure you can split an edge with a point at a specific ratio.
Split Edge with Point (give your ratio U-Value)
__________________
In memory of my friend Hervé: CFD engineer & freerider
-mAx- is offline   Reply With Quote

Old   February 22, 2010, 06:36
Default
  #4
Member
 
smith
Join Date: Apr 2009
Posts: 75
Rep Power: 17
Zweeper is on a distinguished road
yes, i know this option. but i can just split it with one point.
i want to divide my edge into several (many) single points, if its possible, with an automatic way.

it will take a long long time if i have to split it manual.
Zweeper is offline   Reply With Quote

Old   February 22, 2010, 07:11
Default
  #5
Super Moderator
 
-mAx-'s Avatar
 
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41
-mAx- will become famous soon enough
Then I don't know, sorry
Maybe it's better to do this in proE
post a picture from ProE, just for curiosity...
You can also import a sketch into gambit, maybe it can help you
__________________
In memory of my friend Hervé: CFD engineer & freerider
-mAx- is offline   Reply With Quote

Old   February 22, 2010, 08:24
Default
  #6
Member
 
smith
Join Date: Apr 2009
Posts: 75
Rep Power: 17
Zweeper is on a distinguished road
The problem is, i created this geometrie with pro engineer.
But after importing my sketch from pro-e to gambit (iges file) i just have two vertices --> one on the trailing and one on the leading edge of my airfoil profiles.

if i now create an boundary layer, my boundary layer is every time on many parts on the inside of my profiles (and i have negative volumes).

i have no idea how i can solve this problem
Attached Images
File Type: jpg Capture.JPG (22.6 KB, 14 views)
Zweeper is offline   Reply With Quote

Old   February 22, 2010, 09:40
Default
  #7
Super Moderator
 
-mAx-'s Avatar
 
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41
-mAx- will become famous soon enough
upload your dbs file on a share server, I will take a look at it tomorrow morning
__________________
In memory of my friend Hervé: CFD engineer & freerider
-mAx- is offline   Reply With Quote

Old   February 22, 2010, 10:33
Default
  #8
Member
 
smith
Join Date: Apr 2009
Posts: 75
Rep Power: 17
Zweeper is on a distinguished road
hey, thats really nice from you.

i uploaded it here:
http://rapidshare.com/files/354266564/GAMBIT.5928.rar




the outer box is the wind tunnel and the inner box around the wings is my interior. the geometry is created in mm and the first boundary layer cell should have an size of 0.0000014.


maybe you could also give me an inspiration for a good mesh for this problem?




kind regards!
Zweeper is offline   Reply With Quote

Old   February 23, 2010, 02:01
Default
  #9
Super Moderator
 
-mAx-'s Avatar
 
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41
-mAx- will become famous soon enough
Ok I check your geometry, and you don't need to split your edge into several small ones.
What you need BEFORE applying your BL is to mesh you edges.
Then you don't have any problem (cf: attachment)
If you can spend some tiem on your mesh, you may create a full hexa mesh. But it won't be meshed on the fly (I mean you need surface decomposition, eg: splits)
PS: I didn't use your BL-size restriction, and for info Gambit works without any unity (your mesh has to be scaled in your solver)
Attached Images
File Type: jpg BL.jpg (103.5 KB, 23 views)
__________________
In memory of my friend Hervé: CFD engineer & freerider
-mAx- is offline   Reply With Quote

Old   February 23, 2010, 05:18
Default
  #10
Member
 
smith
Join Date: Apr 2009
Posts: 75
Rep Power: 17
Zweeper is on a distinguished road
okay, so you just meshed the edges, added the boundary layer and meshed then the whole interior right?
but i guess the interval count of the edges has to be very high to provide a good enough accuracy or?


did you used gambit as well?
maybe you can also provide your meshed file on a open host server?


kind regards and thanks so far!
Zweeper is offline   Reply With Quote

Old   February 23, 2010, 06:45
Default
  #11
Super Moderator
 
-mAx-'s Avatar
 
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41
-mAx- will become famous soon enough
Sure I used Gambit.
It takes really 10min to mesh the center face:
*mesh the airfoil edges with interval 1 (I assume you have to refine especially at the trailing edge)
*create the BL, and adapt the first layer size with your wish
*create a SF with Meshed option, picke the airfoil edges as source, set the growth rate with 1.2 and the max. size with 20 for instance
That's it, and after you may refine your mesh by interacting with SF parameters.
__________________
In memory of my friend Hervé: CFD engineer & freerider
-mAx- is offline   Reply With Quote

Old   February 23, 2010, 15:32
Default
  #12
Member
 
smith
Join Date: Apr 2009
Posts: 75
Rep Power: 17
Zweeper is on a distinguished road
okay, one question, what do you mean with SF? smoothed face? sry
Zweeper is offline   Reply With Quote

Old   February 23, 2010, 15:36
Default
  #13
Super Moderator
 
-mAx-'s Avatar
 
Maxime Perelli
Join Date: Mar 2009
Location: Switzerland
Posts: 3,297
Rep Power: 41
-mAx- will become famous soon enough
Size Function
__________________
In memory of my friend Hervé: CFD engineer & freerider
-mAx- is offline   Reply With Quote

Old   February 24, 2010, 05:53
Default
  #14
Member
 
smith
Join Date: Apr 2009
Posts: 75
Rep Power: 17
Zweeper is on a distinguished road
okay thank you, i will try this in the evening!
Zweeper is offline   Reply With Quote

Old   February 25, 2010, 14:28
Default
  #15
Member
 
smith
Join Date: Apr 2009
Posts: 75
Rep Power: 17
Zweeper is on a distinguished road
it works perfectly! thanks a lot!
Zweeper is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
[snappyHexMesh] SnappyHexMesh for internal Flow vishwa OpenFOAM Meshing & Mesh Conversion 24 June 27, 2016 08:54
[snappyHexMesh] external flow with snappyHexMesh chelvistero OpenFOAM Meshing & Mesh Conversion 11 January 15, 2010 19:43
how to split hex mesh in icem with desired height? adam2008 ANSYS Meshing & Geometry 3 August 27, 2009 14:59
split functioin in CCM+ Peter Specht Siemens 1 March 5, 2008 08:14
fluent add additional zones for the mesh file SSL FLUENT 2 January 26, 2008 11:55


All times are GMT -4. The time now is 17:18.