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[blockMesh] Bad link between blocks

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Old   July 2, 2014, 11:48
Question Bad link between blocks
  #1
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Victorien
Join Date: Jun 2014
Location: Grenoble, France
Posts: 4
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Hi everybody,

I'm beginner at OpenFOAM, and I face this problem in heat Transfer. I suppose it comes from the geometry I use :

It is composed by a main block (1x1x1), a small cylinder with a fixed temperature (50 K) at its end, and a small block with a fixed gradient at its end (100 W.m^-2). My solver is very simple :

Code:
solve
            (
                rho*cp*fvm::ddt(T)
                - fvm::laplacian(k,T)
            );
where rho, cp and k have for value 1.

I've also fixed the temperature on the top-left side on the first picture at -10 K.

But in the second picture, the main block is at -10 K, and the two others "made their way alone". How can I improve that ?

I saw that with multiple blocks we can merge the faces or match them. It's why I didn't show theses faces in the boundary conditions, then blockMesh can identifie the faces don't form an external boundary and then combine them.

There ir the code of the blockMeshDict :
Code:
convertToMeters 1;
Lx 1.0;
Ly 1.0;
Lz 1.0;
Mx 0.5;
My 0.5;
Mz 0.5;
N 1.5;
vertices        
(
    (0 0 0) //0
    ($Lx 0 0) //1
    ($Lx $Ly 0) //2
    (0 $Ly 0) //3
    (0 0 $Lz) //4
    ($Lx 0 $Lz) //5
    ($Lx $Ly $Lz) //6
    (0 $Ly $Lz) //7
    ($Mx $My $Lz) //8
    ($Lx $My $Lz) //9
    ($Mx $Ly $Lz) //10
    ($Mx $My $N) //11
    ($Lx $My $N) //12
    ($Lx $Ly $N) //13
    ($Mx $Ly $N) //14
    	//cylinder
    (0 0.5 0) //15
    (0 0.5 0.5) //16
    (-0.5 0.5 0.5) //17
    (-0.5 0.5 0) //18
    (0 1 0.5) //19
    (-0.5 1 0.5) //20
    (-0.5 1 0) //21
);

blocks          
(
    hex (0 1 2 3 4 5 6 7) (20 20 20) simpleGrading (1 1 1)
    hex (8 9 6 10 11 12 13 14) (10 10 10) simpleGrading (1 1 1)
    hex (15 16 17 18 3 19 20 21) (5 5 5) simpleGrading (1 1 1)
);

edges           
(
	arc 0 1 (0.5 -0.5 0.0)
	//cylinder
	arc 15 16 (0 0.3964 0.25)
	arc 16 19 (0 0.75 0.6035)
	arc 17 18 (-0.5 0.3964 0.25)
	arc 18 21 (-0.5 0.75 -0.1035)
	arc 21 20 (-0.5 1.1035 0.25)
	arc 20 17 (-0.5 0.75 0.6035)
);

boundary
(
    fixedT
    {
        type patch;
        faces
           (
              (1 2 6 5)
           );
    }
    fluxW
    {
    	type patch;
    	faces
	    (
		(17 20 21 18)
     	    );
     }
     fluxZ
     {
     	type patch;
     	faces
     	    (
     		(11 12 13 14)
     	    );
     }
);
and the code of T :
Code:
dimensions      [0 0 0 1 0 0 0];



internalField   uniform 0;

 

boundaryField

{

   fixedT

	{

		type fixedValue;

		value uniform -10;

	}

   fluxW //On the small circle

	{

		type fixedValue;

		value uniform 50;

	}

   fluxZ //On the small square

	{

		type fixedGradient;

		gradient uniform 100;

	}

}

Thank you for your responses,

Victorien
Attached Images
File Type: png t0.png (15.3 KB, 9 views)
File Type: png tf.png (21.6 KB, 7 views)

Last edited by Victorien; July 2, 2014 at 12:18. Reason: Lack of informations
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Old   July 4, 2014, 06:45
Default A begin of answer
  #2
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Victorien
Join Date: Jun 2014
Location: Grenoble, France
Posts: 4
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Hello again,

I found that this case of multiblocks is present in some tutorial examples. For instance, in the interFoam's damBreak, there are five blocks and the resolution goes through them.

I don't think my problem comes from the blockMeshDict, nor from the 0/ rep. Maybe the lack of files like decomposeParDict or setFieldsDict ?

I'm not so comfortable with these things. Can you light me ?

Thank you for your responses,

Victorien
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