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

question about implementing boundary conditions

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 6, 2006, 07:08
Default question about implementing boundary conditions
  #1
saygin
Guest
 
Posts: n/a
I'm confused about implementing wall and symmetry boundary conditions, does anybody have comments about the questions below?

I'm using an Euler (invisid-compressible) 2-D cell-centered FV (general geometry-not cartesian) approach with 3 dummy cells at each boundary. First question is:

Should I find extra solutions on the cell boundary for wall and symmetry b.c.? That means do I have to make the normal component of the velocity zero? Because I'm using dummy nodes and using a mirror image of the conservative variables, except the corresponding momentum has a reverse sign. I think this reverse momentum at the dummy nodes would give me the zero flux and zero normal velocity automatically. I used this technique for cartesian grid case (without any special computations at the boundary cell face) and it worked, in addition to that I'm using a dimension by dimension computation.

Second question is:

Some books say that for symmetry b.c. use the mirror image technique, with making the corresponding momentum negative at the dummy cells. So what is the difference between wall b.c. and symmetry b.c. for this invisid case?

Regards
  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
Implementation of boundary conditions for FVM Tom Main CFD Forum 7 August 26, 2014 05:58
Boundary Conditions Thomas P. Abraham Main CFD Forum 20 July 7, 2013 05:05
boundary conditions and mesh exporting vaina74 Open Source Meshers: Gmsh, Netgen, CGNS, ... 2 May 27, 2010 09:38
Convective Heat Transfer - Heat Exchanger Mark CFX 6 November 15, 2004 16:55
Question on boundary conditions Diego Nogueira Main CFD Forum 3 July 29, 2004 12:17


All times are GMT -4. The time now is 13:42.