Stress Exceeding Maximum Specified Stress

Question - Why does the stress in my part exceed the maximum stress specified in the Global stress Topology Optimization constraint?

Answer - There are 3 reasons to keep in mind:

  1. The global von-mises stress constraint only regards the optimized elements. So it is expected that on excluded elements the stresses are higher than the given value. If the intent is to regard all the stress values in the constraint you have to use a local von-mises stress constraint and select the whole body as the scoped geometry.
  2. The topology optimization uses the "elemental mean" stress values. So in the result of the design validation stage, you should select "Elemental Mean" as "Display Option".
  3. In the design validation stage, if a mesh other than the one used in topology optimization is used, locally high stresses can appear due to different mesh.