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

CEL Function for moment acting on a BC?

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

Reply
 
LinkBack Thread Tools Display Modes
Old   November 3, 2004, 10:58
Default CEL Function for moment acting on a BC?
  #1
NymphadoraTonks
Guest
 
Posts: n/a
I notice that there are several built in functions for outputing the net X,Y and Z flow induced forces acting on a BC.

Is there a way to output the net moments due to flow induced forces acting on a body?

There dont seem to be built in functions for this?

The BC I'm fiddling with describes an anisotropic-shaped hollow cutout in the fluid domain and as such is not amenable to simple point-of-action assumptions.

TIA
  Reply With Quote

Old   November 3, 2004, 17:18
Default Re: CEL Function for moment acting on a BC?
  #2
Glenn Horrocks
Guest
 
Posts: n/a
Hi,

You could make an additional variable of the cross product of the elemental force and the axis you are taking your torques about. Then you can integrate them over the surface and get the total torque.

Glenn Horrocks
  Reply With Quote

Old   November 4, 2004, 02:29
Default Re: CEL Function for moment acting on a BC?
  #3
NymphadoraTonks
Guest
 
Posts: n/a
That's what I thought ...

So no built in function but I can do this in user fortran? You wouldn't be able to do this in a user CEL function I take it?

  Reply With Quote

Old   November 4, 2004, 11:57
Default Re: CEL Function for moment acting on a BC?
  #4
Juan Carlos
Guest
 
Posts: n/a
Take a look at the etc/VARIABLES file in the installation directory. There is a callback named torque that seems to work as the force callback.. It may compute the torque respect the position vector on the global frame.

Juan Carlos
  Reply With Quote

Old   November 10, 2004, 18:01
Default Re: CEL Function for moment acting on a BC?
  #5
Robin
Guest
 
Posts: n/a
The torque is given about a global axis. If you need it about another axis, it is a trivial calculation to do. You simply need to take the torque about each axis and the forces in each direction, then apply simple statics to do the transformation. All of the above are available as CEL integration functions.

Regards, Robin
  Reply With Quote

Reply

Thread Tools
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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Compile problem ivanyao OpenFOAM Running, Solving & CFD 1 October 12, 2012 09:31
ParaView for OF-1.6-ext Chrisi1984 OpenFOAM Installation 0 December 31, 2010 07:42
latest OpenFOAM-1.6.x from git failed to compile phsieh2005 OpenFOAM Bugs 25 February 9, 2010 05:37
Error with Wmake skabilan OpenFOAM Installation 3 July 28, 2009 00:35
Axisymmetrical mesh Rasmus Gjesing (Gjesing) OpenFOAM Native Meshers: blockMesh 10 April 2, 2007 14:00


All times are GMT -4. The time now is 03:56.