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

normal injection from pipe flow

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

Reply
 
LinkBack Thread Tools Display Modes
Old   December 19, 2006, 15:33
Default normal injection from pipe flow
  #1
Fred Song
Guest
 
Posts: n/a
The problem is:

Water flows into a pipe which is closed at another end and has hundreds of holes along the axial length. The injection of water to the surrounding fluid from these holes is the major concern. The meshing of hundreds of holes and the region of the jets seems almost impossible to me. Any suggestions about meshing or alternatiev simulation approaches are highly appreciated!

Thanks and Regards!

Fred

  Reply With Quote

Old   December 19, 2006, 20:30
Default Re: normal injection from pipe flow
  #2
Jim_Park
Guest
 
Posts: n/a
For a first cut you might try making each hole square/rectangular, deltaz by r*delta-theta. The mixing details might not be right, but the gross transfer of mass, momentum and energy due to the injection should be the correct order of magnitude. This would require the number of cells for the pipe surface to be twice the number of holes if the pipe surface had 50% hole area.

I can't imagine how to mesh all those holes in detail - or that the resulting numbers would have a lot more credibility.
  Reply With Quote

Old   December 20, 2006, 03:29
Default Re: normal injection from pipe flow
  #3
JM
Guest
 
Posts: n/a
I did a similar case where I had 1032 holes. meshing this holes of less than 0.08 inch diameter in a geometry of more than 1 meter in dia was impossible. I assumed it as a porous medium and worked very well.

  Reply With Quote

Old   December 20, 2006, 04:14
Default Re: normal injection from pipe flow
  #4
Anton Lyaskin
Guest
 
Posts: n/a
It depends upon what do you want to get - if it's some bulk parameters then you can go for porous medium, and if you want some fine details then you can take a short piece of your pipe with 5-10 holes and periodic boundary conditions
  Reply With Quote

Old   December 20, 2006, 09:30
Default Re: normal injection from pipe flow
  #5
Jim_Park
Guest
 
Posts: n/a
Nice!
  Reply With Quote

Old   December 21, 2006, 05:10
Default Re: normal injection from pipe flow
  #6
msureshkumar
Guest
 
Posts: n/a
Assuming porous media will wrok effectively and you can model all holes as cylinder and define it as fluid.
  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
Pipe Flow Saima CFX 1 January 10, 2011 17:41
Turbulence intensity in fully devloped pipe flow - Reference Shocktrain Main CFD Forum 0 October 14, 2010 06:58
LES of highly heated pipe flow - incorrect results MichalH FLUENT 3 June 3, 2009 05:00
Turbulence in a pipe flow JM Main CFD Forum 4 December 21, 2006 05:04
stepped pipe flow Tom Cloutier Main CFD Forum 0 April 20, 2003 13:19


All times are GMT -4. The time now is 22:10.