CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Running, Solving & CFD

Problem: Diffuser Flow sticks to wall

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

Reply
 
LinkBack Thread Tools Display Modes
Old   February 22, 2012, 05:41
Default Problem: Diffuser Flow sticks to wall
  #1
New Member
 
Victor-S. Eberhart
Join Date: Oct 2011
Posts: 20
Rep Power: 4
vigges is on a distinguished road
Hi all,

I'd like to simulate a flow through a symmetric diffuser. So far, it is a 2D problem, although it's going to be extended to a 3D problem.

As you can see on the picture, my flow sticks to one wall what isn't exactly what I have expected.
The topPatch and bottomPatch are missing on the picture due to the dump's size.

I use simpleFoam (kOmegaSST) in OF 2.1.0 and following BCs:

U
Code:
dimensions      [0 1 -1 0 0 0 0];

internalField   uniform (0 0 0);

boundaryField
{

    inletPatch
    {
        type                        mapped;
        value                       uniform (30.22 0 0);
        interpolationScheme   cell;
        setAverage               true;
        average                    (30.22 0 0);    
    }    
    
    allWallPatches
    {
        type                        fixedValue;
        value                       uniform (0 0 0);    
    }
    
    topPatch //outlet
    {
        type                        zeroGradient;
    }

    bottomPatch //outlet
    {
        type                        zeroGradient;
  }

    frontPatch
    {
        type                        empty;
    }

    backPatch
    {
        type                        empty;
    }

}
p
Code:
dimensions      [0 2 -2 0 0 0 0];

internalField   uniform 0;

boundaryField
{

    inletPatch
    {
        type                        zeroGradient;
    }    

    allWallPatches
    {
        type                        zeroGradient;
    }
    
    topPatch //outlet
    {
        type                        fixedValue;
        value                       uniform 0;
    }

    bottomPatch //outlet
    {
        type                        fixedValue;
        value                       uniform 0;
    }

    frontPatch
    {
        type                        empty;
    }

    backPatch
    {
        type                        empty;
    }

}
nut
Code:
dimensions      [0 2 -1 0 0 0 0];

internalField   uniform 0;

boundaryField
{

    inletPatch
    {
        type                        calculated;
        value                       uniform 0;
    }    
    
    allWallPatches
    {
        type                        nutkWallFunction;
        value                       uniform 0;
    }

    topPatch //outlet
    {
        type                        calculated;
        value                       uniform 0;
    }

    bottomPatch //outlet
    {
        type                        calculated;
        value                       uniform 0;
    }

    frontPatch
    {
        type                        empty;
    }

    backPatch
    {
        type                        empty;
    }

}
k
Code:
dimensions      [0 2 -2 0 0 0 0];

internalField   uniform 2.949;

boundaryField
{

    inletPatch
    {
        type                        fixedValue;
        value                       uniform 2.949;
    }    
    
    allWallPatches
    {
        type                        kqRWallFunction;
        value                       uniform 0;
    }

    topPatch //outlet
    {
        type                        zeroGradient;
    }

    bottomPatch //outlet
    {
        type                        zeroGradient;
    }

    frontPatch
    {
        type                        empty;
    }

    backPatch
    {
        type                        empty;
    }

}
omega
Code:
dimensions      [0 0 -1 0 0 0 0];

internalField   uniform 111.1;

boundaryField
{

    inletPatch
    {
        type                        fixedValue;
        value                       uniform 111.1;
    }    
    
    allWallPatches
    {
        type                        omegaWallFunction;
        value                       uniform 0;
    }

    topPatch //outlet
    {
        type                        zeroGradient;
    }

    bottomPatch //outlet
    {
        type                        zeroGradient;
    }

    frontPatch
    {
        type                        empty;
    }

    backPatch
    {
        type                        empty;
    }

}
Maybe someone has an idea how to fix this.
Thanks
Attached Images
File Type: png diffuser01.png (42.0 KB, 7 views)
vigges is offline   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
simple problem yet complex error: analysis of flow through diffuser karthikn21590 FLUENT 2 January 27, 2012 00:52
Flow not moving - Supersonic/Initial Pressure problem? shankara.2 FLUENT 0 June 9, 2009 20:49
moving wall BC problem Sourabh Main CFD Forum 1 August 8, 2006 07:47
Problem on boundry of two phase flow youngan CFX 0 June 30, 2003 02:32
Wall functions or low-Re models? J. P. Main CFD Forum 7 July 9, 1998 11:11


All times are GMT -4. The time now is 16:40.