[ndtrong]

Hi every one,

I am trying to simulate the Zalesak's Disk with InterFoam. However, I could not find any tutorial and set up for this simulation.
Could anyone can share with me the setting up of this problems.

Thanks and Best regards,

[akidess]

Why do you need a tutorial? It's pretty straight-forward. At which point do you encounter difficulties?

[ndtrong]

Dear Akidess,

Thanks for your comment, I do not know how to setup the initial condition for problem.
Please share with me your experiences for this case. Thanks

[akidess]

Use setFields with a circle with alpha=1 and a rectangle with alpha=0.

[ndtrong]

Dear Akidess,

For the initial setup, I understand that it is assigned with setFields.
However, I do not know how set up velocity following the equation as shown in attached picture.

Can you share with me your experiences on this issues.

Thanks

Originally Posted by akidess

Use setFields with a circle with alpha=1 and a rectangle with alpha=0.

[akidess]

You can easily do that with the community addon funkySetFields.

[ndtrong]

Originally Posted by akidess

You can easily do that with the community addon funkySetFields.

I am new in OpenFOAM and have no experiences using funkySetFields. Could you guide me please.

[akidess]

No. Have a look at the documentation / tutorials first:
http://openfoamwiki.net/index.php/Co...funkySetFields

If you have specific questions I'll answer them.

[ndtrong]

Originally Posted by akidess

No. Have a look at the documentation / tutorials first:
http://openfoamwiki.net/index.php/Co...funkySetFields

If you have specific questions I'll answer them.

I have already install swak4Foam with funkySetFields library included.
For simple, I have also made expression for creating circle inside a square box.
However, I do not know how to make expression for velocity of circle since it has no boundary.
For more detail in discussion, could I share my problem with you via email. My email is ndtrong@hotmail.com, could you contact me there

[ndtrong]

Originally Posted by akidess

No. Have a look at the documentation / tutorials first:
http://openfoamwiki.net/index.php/Co...funkySetFields

If you have specific questions I'll answer them.

Dear Akidess,


I tried to generate a Zaselak's disc by using funkySetFields as:
diskGamma0
{
// field alpha1;
field alpha.water;
expression "1";
condition "pow(pos().x-0.0,2) + pow(pos().y-0.25,2) < pow(0.15,2)";
}

diskGamma1
{
// field alpha1;
field alpha.water;
expression "0";
condition "pos().x > -0.025 && pos().x < 0.025 && pos().y > 0.15 && pos().y < 0.5";
}


However, when I run funkySetFields -time 0, it shows error like this:
--> FOAM FATAL ERROR:
The type of the alpha.water is IOobject. Seems that it doesn't exist. Use 'create'


From function doAnExpression()
in file funkySetFields.C at line 414.

FOAM exiting



Do you have any comments or suggestions for this stuck? Thanks

[akidess]

The file for alpha in the 0 folder must be present (and boundary conditions must be set properly) before you can manipulate it with funkysetfields. I'm guessing that's the problem.

[ndtrong]

Originally Posted by akidess

The file for alpha in the 0 folder must be present (and boundary conditions must be set properly) before you can manipulate it with funkysetfields. I'm guessing that's the problem.

I have a file for alpha in the 0 folder as below:


FoamFile
{
version 2.0;
format ascii;
class volScalarField;
object alpha.water;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions [0 0 0 0 0 0 0];

internalField uniform 0;

boundaryField
{
bottom
{
type zeroGradient;
}

outlet
{
type zeroGradient;
}

walls
{
type zeroGradient;
}

defaultFaces
{
type empty;
}
}

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


Do you have any comments for this declaration?

[akidess]

You say you have a file "alpha", but you are trying to manipulate a file "alpha.water".

[ndtrong]

Originally Posted by akidess

You say you have a file "alpha", but you are trying to manipulate a file "alpha.water".

Dear akidess,


Thanks for your comment, now I can initiate field of alpha.water.


I am trying to initiate the fields of velocity as below:
circleVel
{
variables
(
"vx = cos(pi*pos().x) * sin(pi * pos().y);"
"vy = -sin(pi*pos().x) * cos(pi * pos().y);"
);
field U;
expression "vector(vx, vy, 0)";
}



However, I got following error:
Part: circleVel
Modifying field U of type volVectorField

Putting "vector(vx, vy, 0)" into field U at t = "0" if condition "true" is true

swak4Foam: Allocating new repository for sampledMeshes
swak4Foam: Allocating new repository for sampledGlobalVariables
--> FOAM Warning :
From function ConcretePluginFunction<DriverType>::exists
in file lnInclude/ConcretePluginFunction.C at line 116
Constructor table of plugin functions for FieldValueExpressionDriver is not initialized


--> FOAM FATAL ERROR:
Parser Error for driver FieldValueExpressionDriver at "1.8-9" :"field vx not existing or of wrong type"
"vector(vx, vy, 0)"
^^
---------|

Context of the error:


- Driver constructed from scratch
Evaluating expression "vector(vx, vy, 0)"


From function parsingValue
in file lnInclude/CommonValueExpressionDriverI.H at line 1246.

FOAM exiting



Can you suggest me the way to fix this issue.
Thanks

[akidess]

I think your syntax is bad. Try

circleVel
{
variables "vx = cos(pi*pos().x) * sin(pi * pos().y); vy = -sin(pi*pos().x) * cos(pi * pos().y);";
field U;
expression "vector(vx, vy, 0)";
}

[ndtrong]

Originally Posted by akidess

I think your syntax is bad. Try

circleVel
{
variables "vx = cos(pi*pos().x) * sin(pi * pos().y); vy = -sin(pi*pos().x) * cos(pi * pos().y);";
field U;
expression "vector(vx, vy, 0)";
}

Dear akidess,


Thanks for your comments. However, it still shows errors as before:

--> FOAM FATAL ERROR:
Parser Error for driver FieldValueExpressionDriver at "1.8-9" :"field vx not existing or of wrong type"
"vector(vx, vy, 0)"
^^
---------|

Context of the error:


- Driver constructed from scratch
Evaluating expression "vector(vx, vy, 0)"


From function parsingValue
in file lnInclude/CommonValueExpressionDriverI.H at line 1246.

FOAM exiting

The error is caused by another reason, could you suggest me the other options.


Thanks

[akidess]

Please post your complete funkySetDict.

[ndtrong]

Originally Posted by akidess

Please post your complete funkySetDict.

Dear akidess,


Following the complete declaration of my funkySetFieldsDict:


FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object funkySetFieldsDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

expressions
(

circleGamma0
{
field alpha.water;
expression "0";
condition "pow(pos().x-0.5,2) + pow(pos().y-0.75,2) < pow(0.15,2)";
}

circleGamma1
{
field alpha.water;
expression "1";
condition "pow(pos().x-0.5,2) + pow(pos().y-0.75,2) > pow(0.15,2)";
}

circleVel
{
variables "vx = cos(pi*pos().x) * sin(pi * pos().y); vy = -sin(pi*pos().x) * cos(pi * pos().y);";
field U;
expression "vector(vx, vy, 0)";
}

);


Please take a quick look and guide me to resolve this error. Thanks