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[blockMesh] Buice 2D asymetric diffuser

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Old   September 8, 2015, 14:24
Default Buice 2D asymetric diffuser
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Can anyone share Buice 2D asymmetric diffuser (as in the link below) blockMesh file?
http://www.grc.nasa.gov/WWW/wind/val...1/buice01.html
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Old   November 11, 2015, 06:58
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Hi,

I cannot provide a complete working example, but I'm pretty sure this kind of geometry can be achieved using blockMesh along with the codeStream directives. I've tried something similar:
blockMeshCodeStreamDiffuser.png

The mesh above was created with the following blockMeshDict (sorry for the formatting, not supported by any editor I know of):
Code:
/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  2.0.1                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.com                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      blockMeshDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
convertToMeters 1;
 
vertices
(
    (-2 -1 -1.107148718)  // 0
    ( 2 -1 1.107148718)  // 1
    ( 2  1 1.107148718)  // 2
    (-2  1 -1.107148718)  // 3
    (-2 -1 2.5)  // 4
    ( 2 -1 2.5)  // 5
    ( 2  1 2.5)  // 6
    (-2  1 2.5)  // 7
);
 
blocks
(
    hex (0 1 2 3 4 5 6 7) (40 20 20) simpleGrading (1 1 1)
);
 
edges ( 
 
 
       polyLine 0 1 (
 
#codeStream {
 
  codeInclude
    #{
#include "pointField.H"
    #};
 
 
    code
    #{
    const scalar minx = -2.;
  const scalar maxx = 2.;
 const scalar len = maxx-minx;
 const int n = 20;
 const scalar h = len/n;
 for(int i=1; i<n; ++i) {
   const scalar x = minx + i*h;
   const scalar z = atan(x);
   const scalar y = -1.;
   os << "(" << x << " " << y << " "<< z << ") ";
 }  
    #};
   
 } // end of codeStream
   
) // end of polyLine
 
 
 
 
polyLine 3 2 (
 
#codeStream {
 
  codeInclude
    #{
#include "pointField.H"
    #};
 
 
    code
    #{
    const scalar minx = -2.;
  const scalar maxx = 2.;
 const scalar len = maxx-minx;
 const int n = 20;
 const scalar h = len/n;
 for(int i=1; i<n; ++i) {
   const scalar x = minx + i*h;
   const scalar z = atan(x);
   const scalar y = 1.;
   os << "(" << x << " " << y << " "<< z << ") ";
 }  
    #};
   
 } // end of codeStream
   
) // end of polyLine
 
 
 
        
); // end of edges
 
 
boundary
(
);
 
mergePatchPairs
(
);
 
// ************************************************************************* //
For your type of geometry you can either create multiple blocks and define the curve at the bottom piecewise or create a single large block and define the curve using a single function.

Cutter
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Old   November 11, 2015, 08:59
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Hi

Not blockmesh but Salome.

Use the dump file as import script.

The geo i made with base unit so you need to scale your mesh (in x and y) with "H" after exporting.
Attached Images
File Type: jpg buice.jpg (82.9 KB, 42 views)
Attached Files
File Type: txt Buice_2D_Diffuser.py.txt (11.2 KB, 26 views)
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