ME458 - BME487 NONLINEAR FINITE ELEMENT ANALYSIS


OBJECTIVES

 

The theory and application of nonlinear finite element analysis in solid and biosolid mechanics.  Topics: review and generalization of FE concepts, review of solid mechanics, nonlinear incremental analysis, displacement based FE formulation for large displacements and large strains, nonlinear constitutive relations, incompressibility and contact conditions, rubberlike materials, biomechanical materials, solution methods, element libraries.

 

OUTLINE

 

1.    REVIEW OF LINEAR FINITE ELEMENT CONCEPTS

       Discrete systems. Displacement-based finite element method. Potential energy and variational formulation. Weighted residual-Galerkin method. Lagrange multipliers and penalty functions. Isoparametric elements.

        

2.    BASIC CONTINUUM MECHANICS

       Tensors. Stress and strain. Transformations and rotations. Green's and Almansi's strains. Cauchy stress. The polar-decomposition theorem. Second Piola-Kirchhoff stress.

 

3.    FINITE ELEMENTS FOR NONLINEAR SOLID AND STRUCTURAL MECHANICS

       Incremental solution to the nonlinear problem. Newton-Raphson iterations. Total and updated Lagrangian formulation. Incremental equations of motion. Isoparametric finite element discretization (truss, 2D, 3D elements).

 

4.          CONSTITUTIVE RELATIONS

Elastic materials. Hyperelastic and hypoelastic materials. Incompressible and anisotropic materials. Biomechanical characterization.

 

5.    SPECIAL TOPICS IN BIOSOLID MECHANICS

       Mixed element formulation. Modeling residual stresses, muscle activation, and growth. Multiscale modeling for complex structures.

 

6.    IMPLEMENTATION

       Data structures. Incompressible elements: 2 and 3-D, tetrahedral elements.

       Active/passive element formulation. Solution procedures. Postprocessing.


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updated 23 January 2007 By Renato Perucchio