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SimpleFOAM and MRFZones drive me crazy

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Old   February 19, 2014, 22:21
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  #21
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卞凤娇
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Quote:
Originally Posted by Kaskade View Post
cyclic tries to match the points of the periodic surfaces. This often fails, even if the points are only a little off. This is often the case when using snappyHexMesh in combination with cyclic patches. cyclicAMI doesn't match the points and instead performs an interpolation. If the mesh points almost match you should barely notice the interface in the final result.


Go to fvOptions and just add the patches that are within the MRF but don't rotate (the interfaces for example) separated by spaces. example: nonRotatingPatches(AMI1 someWallThatDoesntRotate)
Hi~ I have some problem about interface. I use Pointwise to generate the file such as the boundary,point and so on,but how to use Pointwise generate the interface? Could you help me?
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Old   February 20, 2014, 02:09
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I currently don't own a Pointwise license, so can't really help you.

But something likes periodic interfaces should be in the manual, if it isn't ask your Pointwise Support.
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Old   February 20, 2014, 03:06
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Quote:
Originally Posted by Kaskade View Post
I currently don't own a Pointwise license, so can't really help you.
But something likes periodic interfaces should be in the manual, if it isn't ask your Pointwise Support.
the Ufile
Code:
internalField   uniform (0 8 0);

boundaryField
{
    inlet
    {
        type            fixedValue;
        value           uniform (0 8 0);
    }

    outlet
    {
        type            zeroGradient;
    }

    blade
    {
        type            fixedValue;  
        value           uniform (0 0 0);
    
    symmetry
    {
        type            symmetryPlane;
    }
}
Pfile
Code:
boundaryField
{
    inlet
    {
        type            fixedValue;
        value           uniform 0;
    }

    outlet
    {
        type            fixedValue;
        value           uniform 0;
    }

    blade
    {
        type            zeroGradient;
    }

    symmetry
    {
        type            symmetryPlane;
    }
}
SRFProperties
Code:
SRFModel        rpm;

axis            ( 0 1 0 );

rpmCoeffs
{
    rpm             6;
}
boundary
Code:
4 
( 
    blade 
    { 
        type wall; 
        nFaces 121146; 
        startFace 7649864; 
    } 
    inlet 
    { 
        type patch; 
        nFaces 1172; 
        startFace 7771010; 
    } 
    outlet 
    { 
        type patch; 
        nFaces 1172; 
        startFace 7772182; 
    } 
    symmetry 
    { 
        type symmetryPlane; 
        nFaces 6222; 
        startFace 7773354; 
    }  
)
fvoption
Code:
blade
{
    type            actuationDiskSource;
    active          true;
    selectionMode   cellZone;   
    cellZone        blade;

    actuationDiskSourceCoeffs
    {
        fieldNames       (Urel);
        diskDir     (0 -1 0); 
        Cp          0.53;     
        Ct          0.58;    
        diskArea    300;      
        upstreamPoint   (0 0 0);    
    }
}
toposetdict
Code:
actions
(
    {
        name    blade;
        type    cellSet;
        action  new;
        source  cylinderToCell;
        sourceInfo
        {
            p1 (0 -0.8 0);
            p2 (0 1.2 0);
            radius    10;
        }
    }
     {
         name blade;
         type cellZoneSet;
         action new;
         source setToCellZone;
         sourceInfo
         {
             set blade;
         }
    }
);
The important files are here, could you plz tell me the errors ?When I run the SRFSImpleFoam,it shows as follow:
Code:
Create time

Create mesh for time = 0

Reading field p

Reading field Urel

Reading/calculating face flux field phi

Selecting incompressible transport model Newtonian
Selecting RAS turbulence model kEpsilon
kEpsilonCoeffs
{
    Cmu             0.09;
    C1              1.44;
    C2              1.92;
    sigmaEps        1.3;
}

Creating SRF model

Selecting SRFModel rpm
Creating fintite volume options from fvOptions

Selecting finite volume options model type actuationDiskSource
    Source: blade
    - applying source for all time
    - selecting cells using cellZone blade
    - selected 2989384 cell(s) with volume 630.783

    - creating actuation disk zone: blade


--> FOAM FATAL IO ERROR: 


file: unknown

FOAM exiting
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Old   February 20, 2014, 03:18
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Sorry, I haven't used SRF yet. But it reads like something is wrong with you fvOptions. Or maybe your missing a file. Have you copied one of the tutorials as a starting point?

It is common practice to set p to zeroGradient at the inlet and fixedValue at the outlet. Just like you did with U but inverted.
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Old   February 20, 2014, 03:56
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Quote:
Originally Posted by Kaskade View Post
Sorry, I haven't used SRF yet. But it reads like something is wrong with you fvOptions. Or maybe your missing a file. Have you copied one of the tutorials as a starting point?

It is common practice to set p to zeroGradient at the inlet and fixedValue at the outlet. Just like you did with U but inverted.
Thank you!Onno.Yeah! I really dont konw how to set the fvoption file,especially the type and its coefficient.As to say missing a file,which file is missing?the one to difine the rotate zone? I konw that the MRF solver need a MRFZones file,but I can find it in the SRFtutorials`
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Old   February 20, 2014, 04:06
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MRFZones has been merged into the fvOptions, at least when we are talking about the mainline OpenFOAM.

Compare your case-directory to the tutorials of the solver you are using.
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Old   February 20, 2014, 04:54
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Quote:
Originally Posted by Kaskade View Post
MRFZones has been merged into the fvOptions, at least when we are talking about the mainline OpenFOAM.

Compare your case-directory to the tutorials of the solver you are using.
My case directory seems to miss no file ,comparing with the tutorials,but I am wonder whether the problem lies on the mesh, because the pointwise mesh doesnt have the interface.but when I run the checkmesh,though the poor quality,it seems no influence to if the case running but if the case convergence.
Quote:
Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
points: 1777385
faces: 7779576
internal faces: 7649864
cells: 3111587
faces per cell: 4.9587
boundary patches: 4
point zones: 0
face zones: 0
cell zones: 1

Overall number of cells of each type:
hexahedra: 1305360
prisms: 263592
wedges: 0
pyramids: 108780
tet wedges: 0
tetrahedra: 1433855
polyhedra: 0

Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
Patch Faces Points Surface topology
blade 121146 113789 ok (closed singly connected)
inlet 1172 626 ok (non-closed singly connected)
outlet 1172 626 ok (non-closed singly connected)
symmetry 6222 5529 ok (non-closed singly connected)

Checking geometry...
Overall domain bounding box (-22.2481 -7 -22.5744) (22.4732 52 22.1489)
Mesh (non-empty, non-wedge) directions (1 1 1)
Mesh (non-empty) directions (1 1 1)
Boundary openness (5.9717e-16 -9.47486e-17 -2.49412e-16) OK.
Max cell openness = 9.19727e-16 OK.
Max aspect ratio = 50.7014 OK.
Minimum face area = 1.79658e-07. Maximum face area = 3.49164. Face area magnitudes OK.
Min volume = 4.57575e-11. Max volume = 1.86566. Total volume = 92347.8. Cell volumes OK.
Mesh non-orthogonality Max: 81.4667 average: 17.3853
*Number of severely non-orthogonal (> 70 degrees) faces: 266.
Non-orthogonality check OK.
<<Writing 266 non-orthogonal faces to set nonOrthoFaces
Face pyramids OK.
***Max skewness = 10.1108, 4683 highly skew faces detected which may impair the quality of the results
<<Writing 4683 skew faces to set skewFaces
Coupled point location match (average 0) OK.
Mesh OK.
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Old   March 4, 2014, 23:59
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Hi Jiaojiao,

Quote:
Originally Posted by jiaojiao View Post
Thank you!Onno.Yeah! I really dont konw how to set the fvoption file,especially the type and its coefficient.As to say missing a file,which file is missing?the one to difine the rotate zone? I konw that the MRF solver need a MRFZones file,but I can find it in the SRFtutorials`
For MRFSimpleFoam, it needs a MRFZone. And only the cells in this zone are in the rotating reference frame. However, for SRFSimpleFoam, there is no such a zone. All the cells in the SRF-solver are in the rotating reference frame and all the cells are rotating with the frame. So in SRF-solver, you need to re-define your boundary conditions.

Thanks
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