|
[Sponsors] |
August 19, 2000, 15:19 |
boundary conditions
|
#1 |
Guest
Posts: n/a
|
Dear friends, My question is very simple. If in a numerical problem a symetry exists, so when we are treating a node on the symertic axis we will consider all the heat flux (in and out) the control volume surrounding the node as equal to zero. Is it correct or no?? Is true even if we take half of the calculation domain?? thanx for ur contribution
|
|
August 19, 2000, 22:20 |
Re: boundary conditions
|
#2 |
Guest
Posts: n/a
|
(1). The symmetry condition simply says that the solution is symmetric with respect to the symmetry axis, or symmetry plane. Only at that particular location. (2). The other way to say is that the solution has a zero gradient normal to the symmetry axis at that point. (3). How you place the cell at the boundary is a different story. For conduction, with the temperature gradient equal to zero at the symmetry axis, there is no heat transfer at that location normal to the axis. (4).For a typical control volume, you will have three other surfaces for 2-D and 5 other surfaces for 3-D cases. The symmetry condition controls only one surface, not all surfaces.
|
|
August 24, 2000, 18:42 |
Re: boundary conditions
|
#3 |
Guest
Posts: n/a
|
The heat flux through a certain face will be zero only if the face is contained in the plane of symmetry (is a part of it).
If you have a node (and not a face of the control volume) on the symmetry plane then the heat flux is not neccessary zero in the faces of the control volume. I any Basic Book of CFD is the proper treatment of the boundary in such case ( see Patankar for instance) |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Impinging Jet Boundary Conditions | Anindya | Main CFD Forum | 25 | February 27, 2016 13:58 |
symmetry boundary conditions in cfx | lost.identity | CFX | 41 | May 22, 2013 08:21 |
OpenFOAM Variable Velocity Boundary Conditions | NickolasPl | OpenFOAM Programming & Development | 2 | May 19, 2011 06:37 |
[Netgen] boundary conditions and mesh exporting | vaina74 | OpenFOAM Meshing & Mesh Conversion | 2 | May 27, 2010 10:38 |
[Commercial meshers] Trimmed cell and embedded refinement mesh conversion issues | michele | OpenFOAM Meshing & Mesh Conversion | 2 | July 15, 2005 05:15 |