[GavinRe]

Hi, I'm creating a 3d blockMesh for multiphase (water air) simulation.

Here is the error i'm getting during checkMesh:

    Face pyramids OK.
 ***Max skewness = 553.937, 724 highly skew faces detected which may impair the quality of the results
  <<Writing 724 skew faces to set skewFaces
    Coupled point location match (average 0) OK.

Failed 2 mesh checks.

End

and when I run paraFoam, this happened. Refer to image attached.
1.PNG

Can anyone please point out at which part from my blockMeshDict should i ammend?

/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  9
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    format      ascii;
    class       dictionary;
    object      blockMeshDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

convertToMeters 0.01;

vertices //(x y z)
(
    (-18  0  10) //0
    (  -5  0  10) //1
    ( 15  0  10) //2 
    ( 60  0  10) //3
    
    (  0   0   5) //4
    ( 10  0   5) //5
    (  0 30   5) //6
    ( 10 30   5) //7
    
    (-18 54  10) //8
    ( -5 54  10) //9
    ( 15 54  10) //10
    ( 60 54  10) //11
    
    (-18  0 -10) //12
    ( -5  0 -10) //13
    ( 15  0 -10) //14
    ( 60  0 -10) //15
   
    (  0  0  -5) //16
    ( 10  0  -5) //17
    (  0 30  -5) //18
    ( 10 30  -5) //19

    (-18 54 -10) //20
    ( -5 54 -10) //21
    ( 15 54 -10) //22
    ( 60 54 -10) //23
	
    (-18 30  10) //24
    ( -5 30  10) //25
    ( 15 30  10) //26
    ( 60 30  10) //27
	
    (-18 30 -10) //28
    ( -5 30 -10) //29
    ( 15 30 -10) //30
    ( 60 30 -10) //31
	
    (  0 54  10) //32
    ( 10 54  10) //33 
    (  0 54 -10) //34
    ( 10 54 -10) //35

);

blocks
(
    // pre-block
    hex ( 0  1  13  12  24 25 29 28) (40 20 20) simpleGrading (1 1 1) 
    hex ( 24 25 29 28 8 9 21 20) (40 20 20) simpleGrading (1 1 1) 
	
   // obstacle blocks
   hex ( 1  2  5  4 25 26  7  6) (20 20 20) simpleGrading (1 1 1)   
   hex (25 26  7  6  9 10 33 32) (20 20 20) simpleGrading (1 1 1)

    hex ( 1  4 16 13 25  6 18 29) (20 20 20) simpleGrading (1 1 1) 
    hex (25  6 18 29  9 32 34 21) (20 20 20) simpleGrading (1 1 1)

    hex ( 6  7 19 18 32 33 35 34) (20 20 20) simpleGrading (1 1 1) 

    hex ( 5  2 14 17  7 26 30 19) (20 20 20) simpleGrading (1 1 1) 
    hex ( 7 26 30 19 33 10 22 35) (20 20 20) simpleGrading (1 1 1)

    hex (14 13 16 17 30 29 18 19) (20 20 20) simpleGrading (1 1 1) 
    hex (30 29 18 19 22 21 34 35) (20 20 20) simpleGrading (1 1 1) 
	
    // post-block
    hex ( 2  3 15 14 26 27 31 30) (40 20 20) simpleGrading (1 1 1)
    hex (26 27 31 30 10 11 23 22) (40 20 20) simpleGrading (1 1 1)
);

edges
//axis-z is chord length
//centre of the circle is (7.5,0,0)
(
	arc  4  5 (  	5   0   7.071)
	arc  5 17 (12.071   0    	0)
	arc 17 16 (  	5   0  -7.071)
	arc 16  4 (-2.071  	0     	0)
	
	arc  6  7 (  	5  30   7.071)
	arc  7 19 (12.071  30     	0)
	arc 19 18 (  	5  30  -7.071)
	arc 18  6 (-2.071  30     	0)
);

boundary
(
    leftWall //inlet
    {
        type wall;
        faces
        (
            ( 0 24 28 12)
	    (24  8 20 28)
			
        );
    }
    rightWall //outlet
    {
        type wall;
        faces
        (
            (27 3 15 31)
	    (11 27 31 23)
        );
    }
    lowerWall
    {
        type wall;
        faces
        (
            ( 0  1 13 12)
	    ( 1  4 16 13)
	    ( 1  2  5  4)
	    (14 13 16 17)
	    ( 5  2 14 17)
	    ( 2  3 15 14)
	
			//cylinderWall 
			( 4  6 18 16)
			( 6  7 19 18)
			( 5  7 19 17)
			( 5  4  6  7)
			(16 17 19 18)
        );
    }
    atmosphere
    {
        type patch;
        faces
        (
			( 8 20 21  9)
			( 9 10 33 32)
			( 9 32 34 21)
			(33 10 22 35)
			(22 21 34 35)
			(10 22 23 11)
			(32 33 35 34)
        );
    }
	frontAndBack 
	{
		type wall;
		faces
		(	
			//frontWall
			( 0  1 25 24)
			(24 25  9  8)
			( 1  2 26 25)
			(25 26 10  9)
			( 2  3 27 26)
			(26 27 11 10)
			
			//backWall
			(12 13 29 28)
			(28 29 21 20)
			(13 14 30 29)
			(29 30 22 21)
			(14 15 31 30)
			(30 31 23 22)
		);
	}
	defaultFaces
	{
		type empty;
		faces
		(
			
		);
	}
);

mergePatchPairs
(
);

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