issue meshing a building with balconies
 

I'm encountering difficulties in meshing a building that includes balconies.

Figure 1 displays a shaded depiction of a portion of the building, while Figure 2 presents the building in STL format. In Figure 1, discernible white lines (representing edges) originate from buildings_edgeMesh.obj, extracted via surfaceFeatureExtract.

Figure 3 shows the mesh achieved using snappyHexMesh. The issue seems to be that the mesh do not snap to the feature edges, to cause there being wrinkles between the balconies and vertical walls.

Numerous adjustments have been attempted, such as modifying maximum cell number, resolving angles, adjusting feature refinement levels, surface refinement levels, and region refinement levels (see below). While some trials yielded slight improvements, the issue persists (see Figure 3). I think this may be a typical situation people come across, and there might be a setting that has eluded my attention. Could anyone offer insights into this matter? thanks for advance.

resolveFeatureAngle 30;
features {file "building.eMesh"; level 8;}
refinementSurfaces {building {level (6 6); patchInfo { type wall; } }}
refinementRegions {refinementCylinderBuilding { mode distance; levels ((50 5)(100 3));}}

Hello,

It is not clear on your screenshots, but if this is not already done try to keep an aspect ratio of 1 for your background mesh (blockMesh).
Otherwise snappy often struggles to properly snap to geometry.

If possible, you should also try to align your background mesh with your geometry (not necessarily possible depending on your building shape)

I hope this helps,
Yann