CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Meshing & Mesh Conversion

[blockMesh] Bad link between blocks

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 2, 2014, 11:48
Question Bad link between blocks
  #1
New Member
 
Victorien
Join Date: Jun 2014
Location: Grenoble, France
Posts: 4
Rep Power: 12
Victorien is on a distinguished road
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, 8 views)

Last edited by Victorien; July 2, 2014 at 12:18. Reason: Lack of informations
Victorien is offline   Reply With Quote

Old   July 4, 2014, 06:45
Default A begin of answer
  #2
New Member
 
Victorien
Join Date: Jun 2014
Location: Grenoble, France
Posts: 4
Rep Power: 12
Victorien is on a distinguished road
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
Victorien is offline   Reply With Quote

Reply

Tags
heat transfer, multi blocks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
[Commercial meshers] converting Fluent mesh to openfoam standard mesh deepesh OpenFOAM Meshing & Mesh Conversion 31 March 29, 2017 06:59
[ICEM] meshing-incomplete mesh in part after moving blocks to separate domains Mfaizan ANSYS Meshing & Geometry 8 November 29, 2015 22:11
[ANSYS Meshing] Very thin plate (0.1mm) ICEM CFD bad meshing msormania ANSYS Meshing & Geometry 1 April 30, 2012 08:45
[GAMBIT] Error message: Cannot link faces due to all loops of edges not being specified Aerogirl ANSYS Meshing & Geometry 4 February 19, 2012 09:21
Problems of Duns Codes! Martin J Main CFD Forum 8 August 15, 2003 00:19


All times are GMT -4. The time now is 03:12.