Finite Element Analysis (FEA) is a powerful tool to validate structural integrity. However, it is easy to fall into the trap of believing colorful stress plots without validating the underlying boundary conditions.
FEA splits a solid model into thousands of small elements (a mesh) and solves displacement equations. If the mesh is too coarse, the mathematical models will underestimate stress concentrations, leading to structural failures.
"FEA is a mathematical model, not a physical truth. If your input constraints are off, your results will be dangerous."
Mesh Convergence Studies
To ensure calculations are mathematically stable, designers must run mesh convergence studies. By refining the mesh size locally in areas of high tension, stress values should stabilize. If they continue to rise infinitely, a singularity is present.
Validating Boundary Constraints
Simplifying fixtures or loads can introduce large errors. A bolt connection is rarely a fixed constraint; in reality, it allows deflection. Accounting for material non-linearity and joint contact behavior ensures FEA models mirror real physical forces.