Theory for Thin Layers
Sometimes, there are thin layers between larger domains that cannot be ignored in a structural analysis. The reasons are either because they have significant flexibility or damping properties, or that they may fail. Examples of such layers are glue layers, O-rings, and gaskets.
When the layer is thin compared to other dimensions of the structure, it is difficult to produce a mesh with acceptable quality and without compromising the numerical conditioning of the stiffness matrix.
The Thin Layer boundary feature allows to overcome this problem, through simplifications in the definition of the
Deformation Measures
, thus avoiding meshing in the through-thickness direction.
There are three different formulations available for modeling thin layers:
•
Solid Approximation
•
Membrane Approximation
•
Spring Approximation