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

Moving Volumes Problem

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

Reply
 
LinkBack Thread Tools Display Modes
Old   August 4, 2011, 09:54
Default Moving Volumes Problem
  #1
New Member
 
John Gallagher
Join Date: Apr 2009
Posts: 4
Rep Power: 8
johngsl is on a distinguished road
Hi,

I have prepared a street model which has moving volumes (cars). I have looked at the tutorials available for sliding and dynamic mesh, but still cant get my trial model to work.

The current set-up is that the main volume (representative of a street canyon) is run to time X to create a steady state of air flow, and then the moving volumes enter and exit the model from outside the street.

I changed the properties of the 'cars' from a stationary wall to a moving wall. I attached a speed and Z direction and left other properties as default. Also, I turned on the dynamic mesh, a rigid zone for the cars and a deforming zone for the street volume. I know from running the model for a few seconds, that the cars are not moving... what am I doing wrong???

I haven't written a UDF before, but I question whether I need it or not for this model. I am using Fluent 6.3 (old school) with a LES turbulence model.

Can anyone help?

Thanks,
John
johngsl is offline   Reply With Quote

Old   August 5, 2011, 05:41
Default
  #2
Member
 
Adrien Lemoine
Join Date: Jun 2011
Location: Paris,France
Posts: 31
Rep Power: 6
AdrienL is on a distinguished road
Hey,

moving wall in the boundary condition menu is only used with a moving reference frame.
You have to create a UDF defining the movement If you really want to see the car moving it s the only option.

There are good examples of UDF in the Fluent Help (6.3 or 12.1)
If you want me to take a look to help you a bit more, send a picture of the geometry/mesh

Adrien
__________________
-------------------------------------------
Plz add reputation if the answer is correct

A cur vaillant rien d'impossible
------------------------------------------
AdrienL is offline   Reply With Quote

Old   August 5, 2011, 06:09
Default
  #3
New Member
 
John Gallagher
Join Date: Apr 2009
Posts: 4
Rep Power: 8
johngsl is on a distinguished road
Adrien,

Thanks for your response. Ok, I have to create a UDF for the cars. I have this link for "grid motion" which I think is correct (but my UDF should be a lot simpler!).

http://my.fit.edu/itresources/manual...udf/node78.htm

Is this correct?

Unfortunately, I cannot post the picture, can I send it to you via email?

Kind Regards,
John
johngsl is offline   Reply With Quote

Old   August 5, 2011, 13:19
Default
  #4
Member
 
Adrien Lemoine
Join Date: Jun 2011
Location: Paris,France
Posts: 31
Rep Power: 6
AdrienL is on a distinguished road
Hi,

I won't have time this week end to check at your mesh but send me a email and I ll take a look on Monday.

Em@ail : lemoine.adrien@hotmail.fr

Best regards

Adrien
__________________
-------------------------------------------
Plz add reputation if the answer is correct

A cur vaillant rien d'impossible
------------------------------------------
AdrienL is offline   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
Problem of restarting moving meshes with icoDyMFoam rolando OpenFOAM Bugs 8 March 23, 2007 07:18
moving wall BC problem Sourabh Main CFD Forum 1 August 8, 2006 07:47
moving mesh problem walid CD-adapco 6 April 1, 2005 17:31
moving boundary problem Andrea Panizza Main CFD Forum 1 February 26, 2002 16:54
Scale Problem and Moving Walls in PCube/TGrid/Fluent Christian Tollschein Main CFD Forum 8 September 17, 1999 13:01


All times are GMT -4. The time now is 00:22.