In order to simulate the structural behaviour of a stiffened panel, a multilevel procedure has been developed by our group for design in a unified platform, reproducing the flow of information among the different structural departments in industry. The set of design variables can be divided into a group of variables describing the main conceptual layout that affect the dimensions of the model and a second group of variables influencing the material behaviour.

In our method, the panel robustness is described using the second statistical moment (the variance) of the performance function. This concept can be used at any stage, but in order to improve the maximum efficiency in the optimization strategy, robustness evaluation is limited to the preliminary design only.

The multilevel approach presented here can be associated to the family of the multilevel parameterization models. In fact, the optimization problem is decomposed into (at least) two levels of design modification, corresponding to different sets of DV, e.g.:

• Preliminary design level; 
• Detailed design level; 
• Material design level.

 

Multi-level Optimization Algorithm:

• Level 1 Optimization

• Level 2 Robustness Optimization

• Level 3 Optimization