[thegauravonline]

Floating Point Error

original configuration of flapping console working fine in icoFsiElasticNonLinULSolidFoam solver, however when making changes to its geometry i.e. inverting the flap upside down blockMesh generates correct geometry but on execution i get Floating Point Error on the very first iteration of first time step.

What could possibly be the reason.

attaching here the blockMesh files

blockMeshDict Original:

convertToMeters 0.01;

vertices
(
    (-3    0   -2.4)
    (0     0   -2.4)
    (0.04  0   -2.4)
    (6    0   -2.4)
    (-3   1.6  -2.4)
    (0    1.6  -2.4)
    (0.04 1.6  -2.4)
    (6   1.6  -2.4)
    (-3   2.6  -2.4)
    (0    2.6  -2.4)
    (0.04 2.6  -2.4)
    (6   2.6  -2.4)

    (-3    0   2.4)
    (0     0   2.4)
    (0.04  0   2.4)
    (6    0   2.4)
    (-3   1.6  2.4)
    (0    1.6  2.4)
    (0.04 1.6  2.4)
    (6   1.6  2.4)
    (-3   2.6  2.4)
    (0    2.6  2.4)
    (0.04 2.6  2.4)
    (6   2.6  2.4)
);

blocks
(
    hex (0 1 5 4 12 13 17 16) (40 20 1) simpleGrading (0.1 0.2 1)
    hex (2 3 7 6 14 15 19 18) (80 20 1) simpleGrading (10 0.2 1)
    hex (4 5 9 8 16 17 21 20) (40 20 1) simpleGrading (0.1 2 1)
    hex (5 6 10 9 17 18 22 21) (5 20 1) simpleGrading (1 2 1)
    hex (6 7 11 10 18 19 23 22) (80 20 1) simpleGrading (10 2 1)
);

edges
(
);

patches
(
    patch plate
    (
        (1 13 17 5)
        (5 17 18 6)
        (6 18 14 2)
    )
    wall topWall
    (
        (8 20 21 9)
        (9 21 22 10)
        (10 22 23 11)
    )
    wall bottomWall
    (
        (0 1 13 12)
        (2 3 15 14)
    )
    patch outlet
    (
        (3 7 19 15)
        (7 11 23 19)
    )
    wall inlet
    (
        (0 12 16 4)
        (4 16 20 8)
    )
    wall frontAndBackPlanes
    (
	(0 4 5 1)
	(4 8 9 5)
	(5 9 10 6)
	(2 6 7 3)
	(6 10 11 7)
	(12 13 17 16)
	(16 17 21 20)
	(17 18 22 21)
	(14 15 19 18)
	(18 19 23 22)
     )
);

mergePatchPairs
(
);

blockMeshDict 'Inverted'

convertToMeters 0.01;

vertices
(
    (-3   2.6   -0.1)
    (0    2.6   -0.1)
    (0.04 2.6  -0.1)
    (6   2.6   -0.1)
    (-3   1.0  -0.1)
    (0    1.0  -0.1)
    (0.04 1.0  -0.1)
    (6   1.0  -0.1)
    (-3    0  -0.1)
    (0     0  -0.1)
    (0.04  0  -0.1)
    (6    0  -0.1)

    (-3   2.6   0.1)
    (0    2.6   0.1)
    (0.04 2.6   0.1)
    (6   2.6   0.1)
    (-3   1.0   0.1)
    (0    1.0   0.1)
    (0.04 1.0   0.1)
    (6   1.0   0.1)
    (-3    0    0.1)
    (0     0    0.1)
    (0.04  0    0.1)
    (6    0    0.1)
);

blocks
(
    hex (0 1 5 4 12 13 17 16) (40 40 1) simpleGrading (0.1 0.2 1)
    hex (5 6 10 9 17 18 22 21) (5 20 1) simpleGrading (1 2 1)
    hex (2 3 7 6 14 15 19 18) (80 40 1) simpleGrading (10 0.2 1)
    hex (4 5 9 8 16 17 21 20) (40 20 1) simpleGrading (0.1 2 1)
    hex (6 7 11 10 18 19 23 22) (80 20 1) simpleGrading (10 2 1)
);

edges
(
);

patches
(
    patch plate
    (
        (1 5 17 13)
        (5 6 18 17)
        (6 2 14 18)
    )
    wall topWall
    (
        (8 9 21 20)
        (9 10 22 21)
        (10 11 23 22)
    )
    wall bottomWall
    (
        (0 12 13 1)
        (2 14 15 3)
    )
    patch outlet
    (
        (3 15 19 7)
        (7 19 23 11)
    )
    wall inlet
    (
        (4 8 20 16)
	 (0 4 16 12)
       
    )
    wall frontAndBackPlanes
    (
	(0 1 5 4)
	(4 5 9 8)
	(5 6 10 9)
	(2 3 7 6)
	(6 7 11 10)
	(12 16 17 13)
	(16 20 21 17)
	(17 21 22 18)
	(14 18 19 15)
	(18 22 23 19)
     )
);

mergePatchPairs
(
);

Error:

Time = 0.001

Selecting coupling scheme Aitken

Time = 0.001, iteration: 1
Current fsi under-relaxation factor: 0.01
Maximal accumulated displacement of interface points: 0
Courant Number mean: 0 max: 0.245296 velocity magnitude: 2.5
DILUPBiCG:  Solving for Ux, Initial residual = 1, Final residual = 8.4538e-08, No Iterations 2
DILUPBiCG:  Solving for Uy, Initial residual = 0.999966, Final residual = 1.7792e-07, No Iterations 4
GAMG:  Solving for p, Initial residual = 1, Final residual = 7.80704e-07, No Iterations 86
GAMG:  Solving for p, Initial residual = 1.98235e-09, Final residual = 1.88759e-09, No Iterations 1
time step continuity errors : sum local = 5.84421e-10, global = 1.62721e-10, cumulative = 1.62721e-10
GAMG:  Solving for p, Initial residual = 0.00487597, Final residual = 7.22372e-07, No Iterations 42
GAMG:  Solving for p, Initial residual = 8.50265e-07, Final residual = 8.30156e-07, No Iterations 1
time step continuity errors : sum local = 2.19309e-07, global = -6.11314e-08, cumulative = -6.09687e-08
Setting traction on solid patch
Total traction force = (0.228999 0.222553 0)
Floating point exception

Please help!!!

[tas38]

What is the output of checkMesh?

[thegauravonline]

Originally Posted by tas38

What is the output of checkMesh?

checkMesh

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
    all points:           15052
    live points:          15052
    all faces:            29425
    live faces:           29425
    internal faces:       14375
    cells:                7300
    boundary patches:     6
    point zones:          0
    face zones:           1
    cell zones:           0

Overall number of cells of each type:
    hexahedra:     7300
    prisms:        0
    wedges:        0
    pyramids:      0
    tet wedges:    0
    tetrahedra:    0
    polyhedra:     0

Checking topology...
    Boundary definition OK.
    Point usage OK.
    Upper triangular ordering OK.
    Face vertices OK.
    Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces ...
    Patch               Faces    Points   Area [m^2]  Surface topology                  
    plate               85       172      6.48e-05    ok (non-closed singly connected)  
    topWall             125      252      0.00018     ok (non-closed singly connected)  
    bottomWall          120      244      0.0001792   ok (non-closed singly connected)  
    outlet              60       122      5.2e-05     ok (non-closed singly connected)  
    inlet               60       122      5.2e-05     ok (non-closed singly connected)  
    frontAndBackPlanes  14600    15052    0.0046672   ok (non-closed singly connected)  

Checking geometry...
    This is a 3-D mesh
    Overall domain bounding box (-0.03 0 -0.001) (0.06 0.026 0.001)
    Mesh (non-empty, non-wedge) directions (1 1 1)
    Mesh (non-empty) directions (1 1 1)
    Mesh (non-empty, non-wedge) dimensions 3
    Boundary openness (2.22144e-18 9.4564e-18 -5.90821e-16) Threshold = 1e-06 OK.
 ***High aspect ratio cells found, Max aspect ratio: 23062.9, number of cells 7300 Threshold = 1000
  Writing 7300 cells with high aspect ratio to set highAspectRatioCells
    Minumum face area = 2.7668e-08. Maximum face area = 3.79791e-06.  Face area magnitudes OK.
 ***Zero or negative cell volume detected.  Minimum negative volume: -3.04009e-09, Number of negative volume cells: 7300
  Writing 7300 zero volume cells to set zeroVolumeCells
    Mesh non-orthogonality Max: 180 average: 180 Threshold = 70
 ***Number of non-orthogonality errors: 14375.
  Writing 14375 non-orthogonal faces to set nonOrthoFaces
 ***Error in face pyramids: 43800 faces are incorrectly oriented.
  Writing 29425 faces with incorrect orientation to set wrongOrientedFaces
    Max skewness = 4.51793e-05 OK.

Failed 4 mesh checks.

End

[thegauravonline]

Seems like i had faces of solid misoriented in the blockMesh.
Sorted that out.
working fine now