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Old   August 16, 2011, 12:20
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  #161
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Ben Vernieres
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Hi Ralph,

I've been trying to install OF 1.6 on my machine but it seems that is is a complicated task with Ubuntu 11.04...

Is there a way to have shipFoam working on OF1.7 at all ?

Regards,

Ben
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Old   August 16, 2011, 14:02
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Bonjour Ben,

Theoretically you just have to rewrite shipFoam to shipFoam for OF1.7 by changing the pressure terms from p or pd to p_rgh. I tried that but probably messed up the code too much.

Isn't it possible for you to download OF1.6 and install it by using the command "wmake" for the different solvers? Should work I'd guess!

Cheers,

Ralph
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Old   August 16, 2011, 14:18
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Quote:
Theoretically you just have to rewrite shipFoam to shipFoam for OF1.7 by changing the pressure terms from p or pd to p_rgh
, and work with "gh" and "ghf", and modify gravity term in pEqn.H, but remember do not change "p" when evaluate forces in forcesCalc.H.

There is a program under linux to compare files/folders, the name is "Diff Meld", with this one it is not dificult to compare interFoam or interDyfoam with shipFolam and learn how you must do it.

Pablo
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Old   August 16, 2011, 15:18
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Thanks Ralph, Pablo,

If I am to go into the files and modify them, I might just give it a try for OF2.0 don't you think?

Regards,

Ben
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Old   August 17, 2011, 01:46
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Quote:
Originally Posted by pablodecastillo View Post
, and work with "gh" and "ghf", and modify gravity term in pEqn.H, but remember do not change "p" when evaluate forces in forcesCalc.H.

There is a program under linux to compare files/folders, the name is "Diff Meld", with this one it is not dificult to compare interFoam or interDyfoam with shipFolam and learn how you must do it.

Pablo
I should have consulted this forum before I started working around in shipFoam

Ben; I think that OF1.7 and 2.0 are using the same terms. The reason that the original shipfoam is not working for OF1.7 and up is that for OF1.6 the pressure terms were different. Hopefully the OpenCFD-guys will keep all the terms the same so that we can use our modified solvers for a long long time!

Let me know if you have any questions about shipFoam; I'm willing to assist in rewriting the code. Contact me by PM.

Cheers,

Ralph
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Old   August 30, 2011, 10:14
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  #166
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Luc Bordier
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Hi shipfoamers,

I give a try using shipfoam with openFOAM 2.0.x.
I got into trouble because of the pimple loop but i finally succeed to make it work with the former piso loop. (surely not a clean way to do it).

The application seems to be running (without any real validation compared to 1.7 so far), but now i wonder if it's possible to use it with combined dynamicFvMesh for boat displacement and dynamic mesh refinement.

How can i specify the options for both features in the dynamicMeshDict ?

Does anyone has an exemple or guideline to have both features in a same simulation ?

Thanks.
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Old   August 30, 2011, 13:53
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Hello Luc,

You can see some examples for both dictionaries (placed under "constant") below. I think there might also some tutorials for moving meshes.

An explanation of the shipDict-file can be found in the shipFoam folder (which is compiled with wmake)

Good luck!

dynamicMeshDict example

Code:
/*---------------------------------------------------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 1.4 |
| \\ / A nd | Web: http://www.openfoam.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
root "";
case "";
instance "";
local "";
class dictionary;
object motionProperties;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
dynamicFvMesh dynamicMotionSolverFvMesh;
motionSolverLibs ("libfvMotionSolvers.so");
//solver laplacian;
solver velocityLaplacian;
//diffusivity uniform;
// diffusivity directional (1 200 0);
// diffusivity motionDirectional (1 1000 0);
// diffusivity inverseDistance 1(Heavy);
// diffusivity file motionDiffusivity;
diffusivity quadratic inverseDistance 1(hull_OBJECT);
// diffusivity exponential 2000 inverseDistance 1(hull_OBJECT);
// ************************************************************************* //
shipDict example
Code:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 1.5 |
| \\ / A nd | Web: http://www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "constant";
object shipDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
startUpdate 15; //was 5
weightFactor ( 1 2 1 );
springCoeffUpdateInterval 25; //was 25
//writing of additional text file with motion path of CoG
writeCoG yes;
writeInterval 5;
bodies
{
hull_OBJECT
{
aMax 10;
CoG ( 0.137 0.0 -0.1);
bodyRotation (0 0 0); //rotation of motion patch local coordinate system in degrees

//Translation parameters
calcTranslationDOF (0 0 1);
initialVelocity (0 0 0);
constantForce (0 0 0);
mass 35.5;
linearDamping (0 0 0 );
linearSpring (0 0 0);

//Rotation parameters
calcRotationDOF (0 0 0);
initialRotationSpeed (0 0 0);
constantMoment (0 0 0);
momentOfInertia (10 5 10);
linearDamping_rot (0 0 0);
linearSpring_rot (0 0 0);
}
}
//Parameters for Ordinary Differential Equations
ODECoeffs 
{
ODESolver RK;
eps 0.0001;
hEst 0.5;
}
 
// ************************************************************************* //
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Old   August 31, 2011, 03:20
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Luc Bordier
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Hello Ralph,

Thanks for your help.

I guess I'm missing something. I wonder if I can use the dynamicRefineFvMesh within shipFOAM.

So if I undserstand well the refinement settings have to be written in the dynamicMeshDict in a same way than the mesh displacement properties.

My problem is that, if I want to have the mesh displacement fo the boat I have to write in the dynamicMeshDict :

Code:
dynamicFvMesh    dynamicMotionSolverFvMesh;
... followed by the dynamic motion options

But if I want to use dynamic remeshing, I have to write in the dynamicMeshDict :

Code:
dynamicFvMesh    dynamicRefineFvMesh;
... followed by the dynamic refinement options

Writting the two former settings in the same dynamicMeshDict seems not to work, only the dynamic motion seems to be performed.

How can I have the two of them working together (if possible) ?

Thanks.
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Old   August 31, 2011, 03:36
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Ralph Moolenaar
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Hello Luc,

I'm sorry, I missed your point in your previous post.... I guess I was a bit tired yesterday. Unfortunately I have no experience with the mesh refinement option!

Regards,

Ralph
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Old   August 31, 2011, 03:45
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Luc Bordier
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Thanks anyway.
I'll ask on a new thread in case someone could have a solution.
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Old   October 20, 2011, 08:58
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vincent
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Hello

I try to run InterDyMFoam but I have the following error message:

"Restraint verticalSpring: attachmentPt - anchor (0 -12.5 -1) spring length 12.539936204 force (-0 12.5 1) moment (0 0 0)
Restraint axialSpring: angle 0 force (0 0 0) moment (-0 -0 -0)


--> FOAM FATAL ERROR:

Maximum number of sixDoFRigidBodyMotion constraint iterations (50000) exceeded.


From function Foam::sixDoFRigidBodyMotion::applyConstraints(scal ar deltaT)
in file pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotion.C at line 134.

FOAM exiting
"

I attache my pointDisplacement file.

Any idea?

Sheers

Vincent
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Old   October 21, 2011, 06:01
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Hi all

I change my pointDisplacement file for only have a pitch movement. I haven't the error message but after 2 or 3 iteration, the interDyMFoam crash.

What's wrong?

Vincent
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Old   November 22, 2011, 05:52
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Ippokratis
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Hi everyone!

Does anyone knows what modifications should be done to run the 1.7 cases to OF 2.0.x?

Thanks!
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Old   November 22, 2011, 05:57
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Ralph Moolenaar
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I think not so much! I'd just copy your case into a new folder and run your OF2.0x solver. The errors will quickly tell you what goes wrong.

Are you working on the Gothenburg cases?
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Old   March 3, 2012, 10:23
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Hallo,

where can i get the latest Version of shipFoam? The only one i found was 1.6.2 but there should be a newer Version?

Thanks.
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Old   March 3, 2012, 13:22
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Ralph Moolenaar
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Dear Joeran,

I think that it's faster to download the shipFoam 1.6.2 version and to install OF 1.6ext (which is very simple with the usage of aliases see http://openfoamwiki.net/index.php/Installation section 2.3.3) since nothing has changed in the source code.

What is the reason that you're interested in using shipFoam?

Regards,

Ralph
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Old   May 31, 2012, 04:01
Default Free surface oscillations interFoam
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I am simulating a hydrofoil near the free surface, using interFOAM in 1.6-ext. The surface deformation looks good from a distance, but if you take a closer look, you can see that there are oscillations with wave lengths of about six cells.

I tried following fvSchemes, but none gave improvement. Now I do not know what to try anymore.

Any tips?

Code:
gradSchemes
{
    default         Gauss linear;
}

divSchemes
{
    div(rho*phi,U)   Gauss linear;
    div(phi,alpha)   Gauss vanLeer;
    div(phirb,alpha) Gauss interfaceCompression;
    div(phi,k)       Gauss upwind;
    div(phi,epsilon) Gauss upwind;
    div(phi,R)       Gauss upwind;
    div(R)           Gauss linear;
    div(phi,nuTilda) Gauss upwind;

    div((nuEff*dev(grad(U).T()))) Gauss linear;
}
Code:
gradSchemes
{
    default         Gauss linear;
}

divSchemes
{
    div(rho*phi,U)   Gauss linear;
    div(phi,alpha)   Gauss upwind;
    div(phirb,alpha) Gauss upwind;
    div(phi,k)       Gauss upwind;
    div(phi,epsilon) Gauss upwind;
    div(phi,R)       Gauss upwind;
    div(R)           Gauss linear;
    div(phi,nuTilda) Gauss upwind;

    div((nuEff*dev(grad(U).T()))) Gauss linear;
}
Code:
gradSchemes
{
    default         Gauss linear;
}

divSchemes
{
    div(rho*phi,U)   Gauss upwind;
    div(phi,alpha)   Gauss upwind;
    div(phirb,alpha) Gauss upwind;
    div(phi,k)       Gauss upwind;
    div(phi,epsilon) Gauss upwind;
    div(phi,R)       Gauss upwind;
    div(R)           Gauss linear;
    div(phi,nuTilda) Gauss upwind;

    div((nuEff*dev(grad(U).T()))) Gauss linear;
}
Code:
gradSchemes
{
    default        faceLimited leastSquares 0.5;
}

divSchemes
{
    div(rho*phi,U)   Gauss upwind;
    div(phi,alpha)   Gauss upwind;
    div(phirb,alpha) Gauss upwind;
    div(phi,k)       Gauss upwind;
    div(phi,epsilon) Gauss upwind;
    div(phi,R)       Gauss upwind;
    div(R)           Gauss linear;
    div(phi,nuTilda) Gauss upwind;
    div((nuEff*dev(grad(U).T()))) Gauss linear;
}
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File Type: jpg Screenshot-1.jpg (30.3 KB, 73 views)
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Old   May 31, 2012, 04:12
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  #178
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Try a different mesh with less cells in the stream direction (at least at the free surface) or more cells in transverse direction (or a combination of both ). In the way you'll change the cells shape which could result in a more stable free surface.

Good luck!
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Old   May 31, 2012, 04:55
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  #179
ngj
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Hi Flowris

What does your fvSolution file look like? With respect to schemes, I have been happy using MUSCL for div(rho*phi,U) and div(phi.aplha).

Best regards,

Niels
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Old   May 31, 2012, 06:30
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Ralph, Niels, thanks for the tips. I am currently trying them.

My fvSolution:
Code:
solvers
{
    pcorr PCG
    {
        preconditioner   DIC;
        tolerance        1e-10;
        relTol           0;
        minIter          0;
        maxIter          2000;

    };
    pd PCG
    {
        preconditioner   DIC;
        tolerance        1e-7;
        relTol           0.05;
        minIter          0;
        maxIter          2000;
    };
    pdFinal PCG
    {
        preconditioner   DIC;
        tolerance        1e-7;
        relTol           0;
        minIter          0;
        maxIter          2000;
    };
    U PBiCG
    {
        preconditioner   DILU;
        tolerance        1e-06;
        relTol           0;
        minIter          0;
        maxIter          2000;
    };
    k PBiCG
    {
        preconditioner   DILU;
        tolerance        1e-08;
        relTol           0;
        minIter          0;
        maxIter          2000;
    };
    epsilon PBiCG
    {
        preconditioner   DILU;
        tolerance        1e-08;
        relTol           0;
        minIter          0;
        maxIter          2000;
    };
    R PBiCG
    {
        preconditioner   DILU;
        tolerance        1e-08;
        relTol           0;
        minIter          0;
        maxIter          2000;
    };
    nuTilda PBiCG
    {
        preconditioner   DILU;
        tolerance        1e-08;
        relTol           0;
        minIter          0;
        maxIter          2000;
    };
}

PISO
{
    momentumPredictor yes;
    nCorrectors     3;
    nNonOrthogonalCorrectors 2;
    nAlphaCorr      1;
    nAlphaSubCycles 4;
    cAlpha          2;
}
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