Singularities

Creo Simulate Structure is based on the theory of linear elasticity, which is a useful approximation of physical reality. Linear elasticity allows solutions that have infinite values of displacement or stress. These solutions with infinite values are called singular elastic states and the locations where they occur are called singularities.

At the location of a singularity and in the small area around the singularity, the theoretical elasticity solution is not a valid representation of physical reality because displacement and stress cannot be infinite. Outside the area of the singularity, the theoretical elasticity solution is valid. Structure attempts to represent the singular representation as accurately as possible using polynomial functions.

Singularities cause edges in a model to require a high p-level for convergence, thus resulting in a longer solution time. Some of the most common locations where element singularities can occur include:

• at reentrant corners

• at point loads and constraints

• along line loads and constraints on solids

• at the interface between elements of different properties, materials, or element types

To understand the causes of singularities, see Singularities and Loads or Singularities and Constraints.