Implausible Results
Stresses too high, too low, or physically nonsensical — here are the most common causes.
If you only have 2 minutes
Implausible results are almost always caused by inconsistent units, incorrect boundary conditions, or singularities being mistaken for real stress concentrations.
Check units first
The most common cause of wrong results: inconsistent units. Make sure your geometry (mm), forces (N), and material (MPa) all work together. A typical inconsistency:
- Geometry in mm ✓
- Forces in N ✓
- Young's modulus entered as 210 (GPa) instead of 210,000 (MPa) ✗ → displacements 1000× too large
Check boundary conditions
- Over-constrained → unrealistically low stress (the model is artificially stiff)
- Under-constrained → unrealistically high stress or rigid body movement
Recognise singularities
Unrealistically high stresses at point supports, sharp corners, or load introduction points are singularities — not real stresses. Evaluate stresses away from these locations. Use path plots or area averages rather than peak nodal values.
Never report the peak stress from a singularity as a result. It has no physical meaning and grows without limit as the mesh is refined.
Symmetry check
For a symmetric model under symmetric loading, results should be symmetric. If they're not, the boundary conditions or loads are asymmetric — even if it's not obvious in the viewer.