Finite Element Analysis code:

San Le's Free Finite Element Analysis toolkit (http://www.slffea.com)

• ANSI C code - fast, relatively simple
• Supports several types of FEA, including 3D truss, beam, brick, plate, and shell elements for stress analysis, and also a 3D brick element for thermal analysis. Brick element includes Lagrange formulation of Jaumann Stress rate for modeling large deformations (in addition to linear analysis at lower stresses).
• No preprocessor front-end: Takes input as text files describing:
  1. Material properties
  2. Element connectivities with nodes
  3. Node positions
  4. Applied loads and displacements
• Outputs text files describing solution
• GUI postprocessor: uses OpenGL to provide 3D visualizations of data