Abstract: Structural design of airplane flutter models with both structural and elastic similarity is concerned. It is a reverse problem for proper natural frequencies as well as structural similarity. A new method for designing fuselage flutter model based on topology optimization is presented. This method is developed to form several sets of finite elements with regular geometrical shape, therefore the structural characteristics of the fuselage are properly described. Above these sets, the “sections” of the grid are regarded as basic unites of structure modification, which are independent from the meshed finite elements. Then a finite element model of reinforced skin with regular grid bars is established, thus this constructed model is built similarly to the original structure of aircraft. By using adjacent sensitivity redistribution method combined with bi-directional evolutionary structural optimization method. This structural topology optimization is developed as follows: the frequency is used as a target, the volume is considered as a constraint. Finally this topology optimization method is applied to a cylindrical fuselage flutter model. Results show that the proposed approach is feasible to achieve structure similarity and given natural frequencies, so it provides a useful reference for the design of airplane flutter models.

Key words: Bi-directional evolutionary structural optimization, Flutter models, Structural similarity, Topology optimization