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

[blockMesh] Non-orthogonal cells checkMesh

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   October 23, 2019, 13:18
Default Non-orthogonal cells checkMesh
  #1
Member
 
Nat K
Join Date: Oct 2017
Posts: 68
Rep Power: 9
nskelly is on a distinguished road
Hi,

I am simulating the flow within a cone-plate rheometer (see attached image for geometry). The red region is the fluid which I am simulating and is being meshed using blockMesh. I tried to create the mesh in blocks using an O-grid method.

I am able to mesh the geometry, however, I tend to get a large mesh non-orthogonality value (89) and there are several non-orthogonal faces when I use checkMesh (see below). I have viewed the areas where this occurs I can see these occur at the truncated region as it is a very small region compared to the size of the domain. How can I reduce the non-orthogonality in this region?

checkMesh log

Code:
Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
    points:           10220451
    faces:            30220000
    internal faces:   29780000
    cells:            10000000
    faces per cell:   6
    boundary patches: 3
    point zones:      0
    face zones:       0
    cell zones:       2

Overall number of cells of each type:
    hexahedra:     10000000
    prisms:        0
    wedges:        0
    pyramids:      0
    tet wedges:    0
    tetrahedra:    0
    polyhedra:     0

Checking topology...
    Boundary definition OK.
    Cell to face addressing 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   Surface topology
    airInterface        40000    40800    ok (non-closed singly connected)
    plate               200000   200401   ok (non-closed singly connected)
    cone                200000   200401   ok (non-closed singly connected)

Checking geometry...
    Overall domain bounding box (-0.02 -0.02 0) (0.02 0.02 0.0006983)
    Mesh has 3 geometric (non-empty/wedge) directions (1 1 1)
    Mesh has 3 solution (non-empty) directions (1 1 1)
    Boundary openness (-3.56487e-17 -2.98897e-17 -2.97265e-15) OK.
    Max cell openness = 1.33522e-15 OK.
    Max aspect ratio = 177.943 OK.
    Minimum face area = 8.74406e-13. Maximum face area = 1.09776e-08.  Face area magnitudes OK.
    Min volume = 9.2687e-19. Max volume = 9.87975e-14.  Total volume = 5.7744e-07.  Cell volumes OK.
    Mesh non-orthogonality Max: 89.2769 average: 9.76535
   *Number of severely non-orthogonal (> 70 degrees) faces: 84000.
    Non-orthogonality check OK.
  <<Writing 84000 non-orthogonal faces to set nonOrthoFaces
    Face pyramids OK.
    Max skewness = 0.437164 OK.
    Coupled point location match (average 0) OK.

Mesh OK.

End

Thanks
Attached Files
File Type: pdf Diagram_CFDOnline.pdf (29.1 KB, 45 views)
nskelly is offline   Reply With Quote

Reply

Tags
block mesh, non orthogonal

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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
[blockMesh] Create internal faces as patch in blockMesh m.delta68 OpenFOAM Meshing & Mesh Conversion 14 July 12, 2018 15:43
[snappyHexMesh] sHM too many cells Knapsack OpenFOAM Meshing & Mesh Conversion 2 July 8, 2017 08:41
[snappyHexMesh] snappyHexMesh Segmentation Fault avd28 OpenFOAM Meshing & Mesh Conversion 11 May 11, 2015 21:32
snappyhexmesh remove blockmesh geometry philipp1 OpenFOAM Running, Solving & CFD 2 December 12, 2014 11:58
[Netgen] Import netgen mesh to OpenFOAM hsieh OpenFOAM Meshing & Mesh Conversion 32 September 13, 2011 06:50


All times are GMT -4. The time now is 07:51.