You can use Delaunay's triangulation method to create an FE mesh for any 2D surface. Any openings that are inside the domain should be defined as contour edges. They will not be taken into consideration during creation of the finite element (FE) mesh. After you select Delaunay's method, you then select the contour for which the element mesh will be created.
An example of the FE mesh created using Delaunay's method:

As you define the parameters for Delaunay's method, you can specify the mesh generation method as Delaunay's method alone or with the additional node generation method (Kang's method, using emitters).
Emitters are the user-defined nodes near which the FE mesh will be thickened. The thickening parameters are given as Kang's parameters:
- H0 parameters defining the length of the first wave
- Kang's parameters (H max ,)
Specific parameters of Kang's method represent:
- H max - the length of the second-to-last wave before ending the refinement
- Q - the relation of the length of the next-to-previous wave.
See also:
Examples of creating finite element meshes (plates and shells)