GMSH TO PROCESS STL FOR SNAPPY HEXMESH PATCH

internal - keeps the faceZone as internal faces.The latest version of snappyHexMesh can automatically process the faceZone according to the faceType keyword with the options: While some simulations use a faceZone to define the intersection of two regions, e.g.В fluid and solid regions in a conjugate heat transfer simulation, a faceZone can also be used to define a set of boundary faces. The faces on the internal surface become a set of internal faces under the name of the specified faceZone. Recent versions of snappyHexMesh can conform internal faces to an internal surface geometry, by specifying a faceZone in refinementSurfaces in the configuration of snappyHexMeshDict. New controls have been added where the user can specify the thickness of the first layer and the entire layer region, using the keywords firstLayerThickness and thickness respectively. The top image shows layers from a mesh generated with version 2.1.0, the bottom image is the new improved mesh using version 2.2.0. This results in better layer addition, in particular in narrow regions of a domain, as shown in the figures below. Improvements have been made to the detection of medial surfaces that are used for mesh shrinking during the layer addition process.

GMSH TO PROCESS STL FOR SNAPPY HEXMESH PATCH

The user can deactivate sliding along a particular patch by including that patch in the layers sub-dictionary with nSurfaceLayers 0 Sliding will occur when the angle between the patch on which layers are added and its neighbouring patch is larger than that specified by the slipFeatureAngle entry in the addLayersControls sub-dictionary of snappyHexMeshDict. In the latest version, vertices can slide along a boundary, allowing the layers to be created without pinching. If a user chose to add layers of cells to a given patch, the layers would pinch at the outer edge of the patch. Layer AdditionДuring the layer addition process in previous versions of OpenFOAM, vertices on boundaries were fixed. The implicit method has the advantage of being fully automated. The explicit method offers greater control and, from our experience, provides slightly better feature conformation. For explicitFeatureSnap, detect features between multiple surfaces Use features in castellatedMeshControls Detects (geometric only) features by sampling the surface The additional settings in the snappyHexMeshDict file that relate to the new functionality can be found in examples in the tutorials, and are: // Number of feature edge snapping iterations (disabled if omitted) This is illustrated below where the right image is of a mesh generated with the latest version of snappyHexMesh, compared to the previous version in the left image. The existing explicit method has been extended to handle snapping features that represent the intersection between boundary patches, even if the patches are in the same plane, i.e.В along a flat surface. Rather than snapping directly to an edge geometry, as supplied explicitly in the previous method, the implicit method snaps to a representation of the feature, calculated from local surface topology. Instead, it uses the resolveFeatureAngle keyword entry to identify surface geometric features, e.g.В creases in the geometry. The new implicit method does not require the user to extract features. The method attracts points on the mesh boundary onto nearest points of the supplied feature edge. In the existing method, the user typically extracts feature edges from the geometry surface using the surfaceFeatureExtract utility and then explicitly specifies the features through the features entry in the snappyHexMeshDict file. In this release, we have extended existing feature edge handling, reported previously and have also implemented a new method for handling feature edges.

Gmsh to process stl for snappy hexmesh