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

pipe with buoyantFoam buoyancy, boundary conditions

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 15, 2009, 09:58
Default pipe with buoyantFoam buoyancy, boundary conditions
  #1
Senior Member
 
Join Date: Apr 2009
Location: Karlsruhe, Germany
Posts: 104
Rep Power: 17
Thomas Baumann is on a distinguished road
Dear all,

I try to simulate a pipe flow axis-symmetric. The mesh was generated in Gambit (one cell thick) and converted with fluentMeshToFoam and scaled. After it was made axis-symmetric with the application makeAxialMesh. When running with icoFoam there are no solving problems, but I want to use a heated wall with buoyancy effects, the acceleration is parallel to the pipe. And there I get no solution...

The boundary layers are:

* inlet Eingang
* outlet Ausgang
* wedge (frontAndBack)
* wall (oben)
* axis

The Fluid is air and I try to solve without implementation of turbulence modelling.

But what kind of boundary conditions are neccessary so solve. I read a lot in the forum and tested...


p

dimensions [1 -1 -2 0 0 0 0];

internalField uniform 100000;

boundaryField
{
oben
{
type calculated;
value uniform 100000;
}

axis
{
type empty;
}

frontAndBack
{
type empty;
}

eingang
{
type zeroGradient;
}

ausgang
{
type calculated;
value uniform 100000;
}

symmetry_pos
{
type wedge;
}

symmetry_neg
{
type wedge;
}

symmetry
{
type empty;
}
}

// ************************************************** ***********************

pd

dimensions [1 -1 -2 0 0 0 0];

internalField uniform 0;

boundaryField
{
oben
{
type fixedFluxBuoyantPressure;
value uniform 0;
}

axis
{
type empty;
}

frontAndBack
{
type empty;
}

eingang
{
type zeroGradient;
}

ausgang
{
type fixedFluxBuoyantPressure;
value uniform 0;
}

symmetry_pos
{
type wedge;
}

symmetry_neg
{
type wedge;
}

symmetry
{
type empty;
}
}

// ************************************************** ***********************


U

dimensions [0 1 -1 0 0 0 0];

internalField uniform (3 0 0);

boundaryField
{
oben
{
type fixedValue;
value uniform (0 0 0);
}

symmetry
{
type empty;
}

axis
{
type empty;
}

frontAndBack
{
type empty;
}

ausgang
{
type zeroGradient;
}

eingang
{
type fixedValue;
value uniform (3 0 0);
}

symmetry_pos
{
type wedge;
}

symmetry_neg
{
type wedge;
}
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

T

dimensions [0 0 0 1 0 0 0];

internalField uniform 300;

boundaryField
{
oben
{
type fixedValue;
value uniform 300;
}

symmetry
{
type empty;
}

axis
{
type empty;
}

frontAndBack
{
type empty;
}

ausgang
{
type zeroGradient;
}

eingang
{
type fixedValue;
value uniform 300;
}

symmetry_pos
{
type wedge;
}

symmetry_neg
{
type wedge;
}
}

// ************************************************** *********************** //

Could someone please give me a hint.

Thanks a lot, Thomas Baumann
Thomas Baumann is offline   Reply With Quote

Reply


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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Defining "Neutral" boundary conditions? (force=0) MW FLUENT 5 October 5, 2009 05:55
Please help with flow around car modelling! Tudor Miron CFX 17 March 19, 2004 20:23
Terrible Mistake In Fluid Dynamics History Abhi Main CFD Forum 12 July 8, 2002 10:11
Pipe Flow Boundary conditions Kunal Jain Main CFD Forum 0 September 4, 2001 21:52
fluid flow fundas ram Main CFD Forum 5 June 17, 2000 22:31


All times are GMT -4. The time now is 22:21.