Size Optimization of Stiffeners in Bending Plates

A new approach for the modeling and optimization of bending stiffened plates is presented. Eight node elements are used in the proposed finite element model. The proposed element is hybrid in the sense that it can model both the base plate and the stiffeners, simultaneously. A sizing optimization model aiming at maximizing the natural frequencies of free vibrations at a constant volume of stiffeners is introduced. The method of moving asymptotes is used as the optimization tool. Numerical examples of different plates including an application on wind turbine blades are presented. Results show that the fundamental frequency can be doubled by the proper distribution of stiffeners.