checkMesh - Checks validity of a mesh.
Checks validity of a mesh
- Include bounding box checks
- Include extra topology checks
- Skip checking the mesh topology
- Exclude the 0 directory from the times list
- Select time steps. RANGES follows the time selection rules
- Apply only on the latest time available
- Include the constant directory in the times list
- Run the utility in parallel
-roots "(DIR1 [...DIRN])"
- Directories through which the data are distributed
- Specify a mesh region by its NAME
- Execute the command on the case directory DIR. If not provided, use the current directory
- Skip the execution of the functionObjects
- Display the help and exit
4 Output explanation
The output will be explained based on the checkMesh output for the tutorial $FOAM_TUTORIALS/incompressible/icoFoam/cavity.
1. Mesh statistics
points: 882 internal points: 0 faces: 1640 internal faces: 760 cells: 400 boundary patches: 3 point zones: 0 face zones: 0 cell zones: 0 Overall number of cells of each type: hexahedra: 400 prisms: 0 wedges: 0 pyramids: 0 tet wedges: 0 tetrahedra: 0 polyhedra: 0
2. 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 movingWall 20 42 ok (non-closed singly connected) fixedWalls 60 122 ok (non-closed singly connected) frontAndBack 800 882 ok (non-closed singly connected)
3. Checking geometry...
Overall domain bounding box (0 0 0) (0.1 0.1 0.01) Mesh (non-empty, non-wedge) directions (1 1 0) Mesh (non-empty) directions (1 1 0) All edges aligned with or perpendicular to non-empty directions. Boundary openness (8.47033e-18 -8.47033e-18 -5.901e-17) OK. Max cell openness = 1.35525e-16 OK. Max aspect ratio = 1 OK. Minimum face area = 2.5e-05. Maximum face area = 5e-05. Face area magnitudes OK. Min volume = 2.5e-07. Max volume = 2.5e-07. Total volume = 0.0001. Cell volumes OK. Mesh non-orthogonality Max: 0 average: 0 Non-orthogonality check OK. Face pyramids OK. Max skewness = 1e-08 OK. Coupled point location match (average 0) OK.
- Bounding box
- The minimal box that can contain the mesh
- Non-empty, non-wedge directions
- (1 1 0) means x and y are not empty neither wedges. But z is empty or wedge.
- Non-empty directions
- (1 1 0) means x and y are not empty directions. But z is.
- Aspect ratio
- Face aspect ratio:
- The ratio between the longest and the shortest length.
- Cell aspect ratio:
- If the mesh is pseudo-2D, then it's just the ratio between the biggest and the smallest areas of the cell's bounding box.
- If 3D, then it's the largest between the previous ratio and the result of the following expression:
- , , : are the areas of the bounding box of the cell
- : is the volume of the cell
- Note: aspect ratio 1.0 is the best.
- Cell volumes
- The difference between min and max should be as small as possible (or the evolution should be as smooth as possible - not check for that)
- Mesh non-orthogonality
- Measure the angle between the line connecting two cell centres and the normal of their common face - 0.0 is the best.
- Measure the distance between the intersection of the line connecting two cell centres with their common face and the centre of that face - smaller is better.
4.1 Other Explanations
- DxFoam reader update - post #15 - Hrvoje Jasak comments on the topics of non-orthogonality and skewness.