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

O-GRID generation in ICEM CFD

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 23, 2007, 17:09
Default O-GRID generation in ICEM CFD
  #1
Mohammad Faridul Alam
Guest
 
Posts: n/a
I am facing problem while genearting O-GRID around NACA0012 Airfoil.The problem is: the girdlines on the airfoil are not being perpendicular to the surface of airfoil. I need such mesh where each gridline will be perpendicular to the airfoil.

  Reply With Quote

Old   August 24, 2007, 04:18
Default Re: O-GRID generation in ICEM CFD
  #2
Dr. Flow Squad
Guest
 
Posts: n/a
You should probably go for a C-grid instead. Here's a late post with pictures showing two different block structures. http://www.cfd-online.com/Forum/cfx_...cgi?read=20096 -Dr. Flow Squad http://tinyurl.com/2gkjh8

  Reply With Quote

Old   August 27, 2007, 01:37
Default Re: O-GRID generation in ICEM CFD
  #3
Mohammad Faridul Alam
Guest
 
Posts: n/a
Thanks. I have seen the C-GRIDS. but still the grid lines on the airfoil are not normal to the surface of the airfoil. we are looking for perfectly normal gridlines on the airfoil.
  Reply With Quote

Old   August 27, 2007, 19:18
Default Re: O-GRID generation in ICEM CFD
  #4
Glenn Horrocks
Guest
 
Posts: n/a
Hi,

You can also get nice boundary layer meshes with CFX-Mesh with lots of inflation layers. You can also ensure the gridlines are normal to the airfoil this way too, but be careful at the trailing edge. It is tricky to get the trailing edge to inflate nicely.

Regards, Glenn Horrocks
  Reply With Quote

Old   December 11, 2009, 05:36
Default
  #5
New Member
 
Rauno
Join Date: Apr 2009
Location: San Diego (USA); Pisa (Italy); Munich(Germany)
Posts: 10
Rep Power: 16
fulkrum is on a distinguished road
So,
bottom line is that for an airfoil the O-Grid option (with ICEM CFD) could not be used, due to the topology?
I tried all the possible topology, but I wasn´t able to use the O-Grid option.
On the other hand, following the indication of previous post one can anyway obtain a good quality mesh using parameters (to have the grid perpendicular to thge surface).
Any other experience /suggestion about that?
fulkrum is offline   Reply With Quote

Old   December 11, 2009, 06:14
Default
  #6
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,665
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
Well have a think about it - what will an O grid do at the sharp trailing edge? I will let you work it out from there.

The easiest way to make the grid perpendicular to the surface is to generate a small block at the airfoil surface with a thickness defined by a given normal distance from the airfoil. Then it is easy to do a very nice structured mesh on the airfoil surface, and you move the transition to the far field grid (with its associated poorer quality elements) away from the airfoil.

But with some care you should be able to get the mesh perpendicular to the surface with a standard C-grid. You will just need to look into the parameters and adjustments closely.
ghorrocks is offline   Reply With Quote

Old   December 11, 2009, 16:40
Default
  #7
New Member
 
Rauno
Join Date: Apr 2009
Location: San Diego (USA); Pisa (Italy); Munich(Germany)
Posts: 10
Rep Power: 16
fulkrum is on a distinguished road
Thank you, your message was very instructive.
And yes, the O-grid wouldn't be the best solution, due to the sharp trailing edge.

However, I tried many different topology without been successfull in realizing an O-grid anyway.

Your suggestion is meaningfull and interesting. I fould it not so immediate, but this is surely due to my unexpertise with ICEM.
What I need is something not much complicated still of good quality, since I have to do many simulation on different airfoils.
I wasn't able to find, after a fast search here in the forum, the "best"" approach to mesh an airfoil. Thank you.
fulkrum is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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
CFD Salary CFD Main CFD Forum 17 January 3, 2017 18:09
Import Mesh from ICEM CFD to CFX Andre Almeida CFX 16 April 19, 2016 04:42
need help for generation grid aya FLUENT 11 March 4, 2008 15:46
Problems in grid generation in ICEM Tim CFX 1 September 30, 2006 07:43
Grid Independent Solution Chuck Leakeas Main CFD Forum 2 May 26, 2000 12:18


All times are GMT -4. The time now is 20:44.