Missing BC specification on some external BCs

Description

For models with small surface, sometimes some of the outer surface/s element may get missed when creating wall boundary conditions.

Best practices

1. Make sure all outer wall surface elements are selected.
2. Create wall BC one body at a time.
3. Select the outer surface element using window selection - this will make sure all elements are selected.

Example

Example solver error when model has undefined BC elements:

ERROR: MESH HAS HOLES Note: Boundaries with no surface conditions(triangles) are detected as holes Last node with problems (Id= 56115) is part of SubModelPart GateP1 Verify that all the boundaries of this SubModelPart have assigned surface BC.