Assumptions, Limitations, and Conventions

All numerical simulations rely on assumptions. Understanding these assumptions is essential for building models that represent the physical problem accurately.

For linear static finite element analysis, the common assumptions are:

• Deformations are small compared with the dimensions of the structure.
• Material behavior is linear elastic unless otherwise specified.
• Loads are applied slowly enough that inertial effects can be ignored.
• Boundary conditions remain unchanged during loading.
• The mesh is sufficiently refined to capture relevant gradients in displacement and stress.

The following notation is used throughout the manual:

• Bold lowercase symbols represent vectors.
• Bold uppercase symbols represent matrices or tensors.
• Nodal displacement vectors are commonly denoted by u.
• The global stiffness matrix is denoted by K.
• The global force vector is denoted by f.
• Stress and strain are denoted by sigma and epsilon respectively.