[Jetfire]

hi everyone

I tried simulating a compressor fan using rhoPimpleDyMFoam solver with cyclicAMI similar to the propeller case in tutorials
compressor model was taken from grabCAD and meshed using snappyHexMesh.
My simulation stops after few iterations showing this

solidBodyMotionFunctions::rotatingMotion::transformation(): Time = 0.00456585764 transformation: ((0 0 0) (0.9999348537 (0 0.01141439623 0)))
AMI: Creating addressing and weights between 97715 source faces and 98899 target faces
AMI: Patch source sum(weights) min/max/average = 0.9465117834, 1.489766105, 1.00385493
AMI: Patch target sum(weights) min/max/average = 0, 1.237839515, 0.9988507935
- selecting cells using cellZone rotor
- selected 969022 cell(s) with volume 106.5179144

- selecting cells using cellZone rotor
- selected 969022 cell(s) with volume 106.5179144

I decreased the no. of layers as suggested by some in other related threads , but I'm unable to get rid of the problem. Running checkMesh shows

Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
    points:           2398293
    faces:            6465121
    internal faces:   6099705
    cells:            2046246
    faces per cell:   6.140427886
    boundary patches: 7
    point zones:      0
    face zones:       1
    cell zones:       1

Overall number of cells of each type:
    hexahedra:     1793073
    prisms:        45780
    wedges:        0
    pyramids:      0
    tet wedges:    1205
    tetrahedra:    20
    polyhedra:     206168
    Breakdown of polyhedra by number of faces:
        faces   number of cells
            4   27401
            5   15343
            6   21408
            7   41930
            8   22494
            9   56038
           10   618
           12   13871
           15   6600
           18   460
           21   5

Checking topology...
    Boundary definition OK.
    Cell to face addressing OK.
    Point usage OK.
    Upper triangular ordering OK.
    Face vertices OK.
   *Number of regions: 2
    The mesh has multiple regions which are not connected by any face.
  <<Writing region information to "0/cellToRegion"
  <<Writing region 0 with 1077224 cells to cellSet region0
  <<Writing region 1 with 969022 cells to cellSet region1

Checking patch topology for multiply connected surfaces...
                   Patch    Faces   Points                  Surface topology
            frontAndBack     1800     1922  ok (non-closed singly connected)
                  outlet      900      961  ok (non-closed singly connected)
                   inlet    11880    12105  ok (non-closed singly connected)
                   walls    19521    19937  ok (non-closed singly connected)
             compressor1   134701   160487  ok (non-closed singly connected)
                   rotor    97715    98002  ok (non-closed singly connected)
             rotor_slave    98899    99288  ok (non-closed singly connected)

Checking geometry...
    Overall domain bounding box (-5 -6 -4) (5 4 4)
    Mesh (non-empty, non-wedge) directions (1 1 1)
    Mesh (non-empty) directions (1 1 1)
    Boundary openness (-2.080673282e-18 1.194170072e-15 -1.766463148e-17) OK.
    Max cell openness = 3.489719775e-16 OK.
    Max aspect ratio = 12.24054109 OK.
    Minimum face area = 8.076153166e-05. Maximum face area = 0.1141694343.  Face area magnitudes OK.
    Min volume = 1.05758803e-06. Max volume = 0.03044330579.  Total volume = 774.202411.  Cell volumes OK.
    Mesh non-orthogonality Max: 63.30604426 average: 8.876566052
    Non-orthogonality check OK.
    Face pyramids OK.
    Max skewness = 1.716941667 OK.
    Coupled point location match (average 0) OK.

Mesh OK.

End

Please help me understand what the problem is and how to solve it. snappyHexMeshDict file is attached.

Thanks

[Jetfire]

Can someone please help me with this , I'm stuck with this error for days.

[maHein]

So this error appears after a few iterations? Maybe the axis of rotation is not correct, so that the cells are not rotated correctly?

[Jetfire]

@maHein

Thanks for your reply

For my rotation : origin (0 0 0) and Axis is (0 1 0 ).
Please check the pictures attached and let me know if there are any changes in these parameters.

[maHein]

Origin and axis seem to be okay.

Where are your cyclicAMI interfaces? After the trailing edge of the compressor wheel?

[Jetfire]

Yes

I have enclosed the compressor with a cylinder.
check the pictures attached. Let me know if you need anything else to check what the problem is.

[vasava]

Do you have access to Anysys products? Fluent, Gambit etc??

[Jetfire]

I have access to Ansys ICEM CFD.

[vasava]

The error may be due to the fact that your 'rotor' and 'rotor-slave' do not match at the interface/cyclic-AMI. I usually use Ansys-Meshing to avoid this error and for better matching of boundaries at the interface.

[Jetfire]

@vasava

Thanks for your reply , i figured it out that it was my meshing problem but checkMesh says everything OK. Anyways il try out Ansys icem for meshing.