About Hypotheses

Hypotheses represent boundary conditions which will be taken into account at calculations of meshes or submeshes basing on geometrical objects. These hypotheses allow you to manage the level of detail of the resulting meshes or submeshes: when applying different hypotheses with different parameters you can preset the quantity of meshing elements which will compose your mesh. So, it will be possible to generate a rough or a more refined mesh or submesh.

In MESH there are the following Basic Hypotheses (to introduce them, you operate numerical values):

• 1D Hypotheses (for meshing of edges):
  • Arithmetic 1D
  • Local Length
  • Max Size
  • Deflection 1D
  • Number of segments
  • Start and end length
  • Automatic Length
• 2D Hypotheses (for meshing of faces):
  • Max Element Area
  • Length from Edges
  • Quadrangle Parameters
• 3D Hypothesis (for meshing of volumes):
  • Max Element Volume

Some hypotheses are strictly combined with plug-in meshers and thus, work only with definite algorithms.

• Netgen 2D and 3D hypotheses - work with NetGen algorithm.
• GHS3D Parameters hypothesis - works with GHS3D algorithm.
• GHS3DPRL Parameters hypothesis - works with GHS3DPRL (tepal) algorithm.
• BLSURF Parameters hypothesis - works with BLSURF algorithm.
• Hexotic Parameters hypothesis - works with Hexotic algorithm.

There also exist Additional Hypotheses used together with other hypotheses:

• Propagation of 1D Hypothesis on opposite edges
• Non conform mesh allowed
• Quadratic mesh
• Quadrangle preference
• Triangle preference
• Viscous layers

The choice of a hypothesis depends on:

• the geometrical object (shape) which will be meshed
• the algorithm, which will be selected for meshing of this geometrical object (shape)