[stevenw]

I'm a freshman. I got this problem

#0  Foam::error::printStack(Foam::Ostream&) at ??:?
#1  Foam::sigFpe::sigHandler(int) at ??:?
#2   in "/lib/x86_64-linux-gnu/libc.so.6"
#3  Foam::GaussSeidelSmoother::smooth(Foam::word const&, Foam::Field<double>&, Foam::lduMatrix const&, Foam::Field<double> const&, Foam::FieldField<Foam::Field, double> const&, Foam::UPtrList<Foam::lduInterfaceField const> const&, unsigned char, int) at ??:?
#4  Foam::GaussSeidelSmoother::smooth(Foam::Field<double>&, Foam::Field<double> const&, unsigned char, int) const at ??:?
#5  Foam::smoothSolver::solve(Foam::Field<double>&, Foam::Field<double> const&, unsign

I know there must be some zero in the program, but I can not find it out.

//meshGenApp blockMesh;
convertToMeters 0.01;
//5 mm column diameter
 
//10 cm length
 

   

//Width of middle square section
 
   


//how many cells in the square section   
 
//how many cells from square section to perimeter
 
// how many cells from top to bottom  
 
//defination of outside block




vertices
(
  (-2 -1.5 0) // Vertex layer0 = 0 
  (4 -1.5 0) // Vertex layer1 = 1 
  (4 1.5 0) // Vertex layer2 = 2 
  (-2 1.5 0) // Vertex layer3 = 3 

  (-2 -1.5 0.1) // Vertex layer4 = 4 
  (4 -1.5 0.1) // Vertex layer5 = 5 
  (4 1.5 0.1) // Vertex layer6 = 6 
  (-2 1.5 0.1) // Vertex layer7 = 7 

  (-0.25 -0.25 0) // Vertex sevenoclocksqb = 8 
  (0.25 -0.25 0) // Vertex fiveoclocksqb = 9 
  (0.25 0.25 0) // Vertex oneoclocksqb = 10 
  (-0.25 0.25 0) // Vertex elevenoclocksqb = 11 
   
  (-0.353553390593274 -0.353553390593274 0) // Vertex sevenoclockcb = 12 
  (0.353553390593274 -0.353553390593274 0) // Vertex fiveoclockcb = 13 
  (0.353553390593274 0.353553390593274 0) // Vertex oneoclockcb = 14 
  (-0.353553390593274 0.353553390593274 0) // Vertex elevenoclockcb = 15 

  (-0.25 -0.25 0.1) // Vertex sevenoclocksqt = 16 
  (0.25 -0.25 0.1) // Vertex fiveoclocksqt = 17 
  (0.25 0.25 0.1) // Vertex oneoclocksqt = 18 
  (-0.25 0.25 0.1) // Vertex elevenoclocksqt = 19 
   
  (-0.353553390593274 -0.353553390593274 0.1) // Vertex sevenoclockct = 20 
  (0.353553390593274 -0.353553390593274 0.1) // Vertex fiveoclockct = 21 
  (0.353553390593274 0.353553390593274 0.1) // Vertex oneoclockct = 22 
  (-0.353553390593274 0.353553390593274 0.1) // Vertex elevenoclockct = 23 
);                

blocks
(
//outside block
  hex (0 1 2 3 4 5 6 7) (60 30 1) simpleGrading (1 1 1)
//square block
  hex (8 9 10 11 16 17 18 19) (12 12 1) simpleGrading (1 1 1)

//slice1
  hex (12 13 9 8 20 21 17 16) (12 12 1) simpleGrading (1 1 1)

//slice2
  hex (8 11 15 12 16 19 23 20) (12 12 1) simpleGrading (1 1 1)

//slice3
  hex (11 10 14 15 19 18 22 23) (12 12 1) simpleGrading (1 1 1)

//slice4
  hex (10 9 13 14 18 17 21 22) (12 12  1) simpleGrading (1 1 1)

);


//create the quarter circles
edges
(
  arc 13 12 (0.0 -0.5 0.0)
  arc 12 15 (-0.5 0.0 0.0)
  arc 15 14 (0.0 0.5 0)
  arc 14 13 (0.5 0.0 0.0)

  arc 21 20 (0.0 -0.5 0.1)
  arc 20 23 (-0.5 0 0.1)
  arc 23 22 (0.0 0.5 0.1)
  arc 22 21 (0.5 0 0.1)

);

boundary
(
    upstream
    {
    type patch;
    faces
    (
        (0 4 7 3)
        );
    }

    downstream
    {
    type patch;
    faces
    (
        (2 6 5 1)
        );
    }

    upAndDown
    {
    type empty;
    faces
    (
        (4 5 6 7)
        (0 3 2 1)
        );
    }

    frontAndBack
    {
    type patch;
    faces
    (
        (0 1 5 4)
        (3 7 6 2)
        );
    }
    cylinder
    {
    type wall;
    faces
    (

         (12 13 21 20)
         (12 20 23 15)
         (15 23 22 14)
         (14 22 21 13)    

    );
    }
)

mergePatchPairs
(
);

this is blockMeshDict run without any problem.

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  2.3.0                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volVectorField;
    object      U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //


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

internalField   uniform (0.02 0 0);

boundaryField
{
    upstream
    {
        type        fixedValue;
        value         uniform (0.02 0 0);
    
    }

    downstream
    {
        type            inletOutlet;
    inletValue      uniform (0 0 0);       
    value           $internalField;
    }

    upAndDown
    {
    type        empty;
    
    }

    frontAndBack
    {
        type            slip;
    
    }

    cylinder
    {
    type        fixedValue;
    value        uniform (0 0 0);
    }
}

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

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  2.3.0                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    object      p;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //



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

internalField   uniform 0;

boundaryField
{
    upstream
    {
        type            zeroGradient;
    
    }
  
    downstream
    {
        type            fixedValue;
        value           $internalField;
    }

    upAndDown
    {
    type        empty;
    }

    frontAndBack
    {
        type            zeroGradient;
    }

    cylinder
    {
        type            zeroGradient;
    }
}

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

U and p


if someone could help? I've been spent 3 days on this problem.

[alexeym]

Hi,

Can you also post checkMesh output? Does the error happen at the very start? What is the value of Re in the problem?

[stevenw]

Originally Posted by alexeym

Hi,

Can you also post checkMesh output? Does the error happen at the very start? What is the value of Re in the problem?

hi alexeym,
Thanks a lot for your reply.

No error occurred in checkMesh output. re=1e-06. It is a simulation of flow over a circular cylinder using pisoFoam. The result seemed to be unable to converge. I even used the tutorial setting of icoFoam for this case. Did not work either.

[Svensen]

What is the Courant number in your simulation ?

[ALU]

Hi,

if you have a look at your mesh in parafoam you can see there is definitely something wrong with your mesh. The cylinder should be a hole in the mesh. In /incompressible/pimpleFoam/elipsekkLOmega/ tutorial you can see how a flow around a cylinder can be done with blockmesh.

[stevenw]

Originally Posted by ALU

Hi,

if you have a look at your mesh in parafoam you can see there is definitely something wrong with your mesh. The cylinder should be a hole in the mesh. In /incompressible/pimpleFoam/elipsekkLOmega/ tutorial you can see how a flow around a cylinder can be done with blockmesh.

Hi,Alu

Thanks a lot. I guess that's the point. Now I got the result.

[Gizazu]

Hello everyone.

I´m having problems with pisoFoam to simulate flow around a pier. I´ve seen your posts and comments here.

I´ll try to apply your suggestions, and I´ll report my results for you.

Thanks.

Regards

Gizela

[Gizazu]

Hi. I finally got the simulation working but i have a litlle problems with definition of delta T and courant number which sometimes send back an error during the process. Could you help me with this doubt? What possibly I´m doing wrong?

Another question is that I´m doing a 3D simulation but i can only see Ux and Uz during the calculation. Is that normal?

Please, somebody help me!!!


Regards