CFD Online Logo CFD Online URL
Home > Forums > Main CFD Forum

moving boudnary pressue condition

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

LinkBack Thread Tools Display Modes
Old   July 11, 2005, 05:42
Default moving boudnary pressue condition
Posts: n/a
Does anyone know how to specify pressue (pressure correction) BC for incompressible flow on a moving boudary (esp. where the acceleration is not zero)? Is dp/dn = 0 correct? or should it be dp/dn = -an (an is the boundary acceleration in the normal direction of the moving boundary)? Thanks a lot.
  Reply With Quote

Old   July 11, 2005, 08:35
Default Re: moving boudnary pressue condition
Posts: n/a
The correct condition is the physical one, velocity of the fluid at boundary equals the velocity of the boundary.

How that relates to the pressure depends on the algorithm you've selected.
  Reply With Quote

Old   July 11, 2005, 09:02
Default Re: moving boudnary pressue condition
Posts: n/a
The normal pressure gradient at the boundary will be proportional to the normal acceleration. You can derive it very easily by taking the normal component of the momentum equation at the boundary.
  Reply With Quote

Old   July 11, 2005, 14:54
Default Re: moving boudnary pressue condition
Svetlana Sushchikh
Posts: n/a
To addition : 1. if you apply pressure boundary condition (as recommended), check your surface velocity (see recomendation 1) carefuly. 2. If you want to transfer into body coordinate system, do NOT forget about acceleration.
  Reply With Quote


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
Boundary Conditions Thomas P. Abraham Main CFD Forum 20 July 7, 2013 05:05
boundary condition for define_grid_motion bongo FLUENT 1 June 12, 2013 03:37
Moving boundary condition (opening) kezman CFX 0 November 13, 2009 06:37
Airfoil boundary condition Frank Main CFD Forum 1 April 21, 2008 18:36
Pressure Boundary Condition Matt Umbel Main CFD Forum 0 January 11, 2002 11:06

All times are GMT -4. The time now is 16:45.