| Most modern transportations and aerospace vehicles, are working under vibrations. As a result ofthe vibration load, the displacement, acceleration or the stress of the structure may go to very huge.Sometimes this change may cause a serious tragedy. So it is necessary to do dynamic optimizationdesign and to distribute the mass and the stiffness reasonably to control the structure’s vibrationperformance and improve the structure’s safety performance. An optimization design method ofsectional vibration response which is based on the improved genetic algorithm has been carried out.As a proof, an optimization experiment of the airframe’s acceleration response of GARTEUR iscarried out. On the basis of the optimization design method, an optimization of the dangerous parts ofa bracket is realized.In this paper, the theory and operation of the genetic algorithm are studied, and the specificapplication of the finite element in dynamic optimization is seriously considered. The reaearch isfocused on the airframe of GARTEUR. It tries to reduce the acceleration responses of part of theairframe with sine excitation and random excitation. Redesign the distribution of the mass byimproved genetic algorithm so that the acceleration responses of part of the airframe can be reduced.And the result shows that the acceleration responses of the improved airframe reduce to reasonabledegree than before, it proved that the improved genetic algorithm is effective and the design ideas arefeasible.In addition, for the aircraft fairing bracket structure, due to the stress concentration effect ofthe bending areas, cracks are easy to appear at certain low and high parts while the aircraft is underrandom excitation. In this paper, the re-design is introduced to the bracket-section by using the geneticalgorithm, leading to a considerable degree of stress decreases at the dangerous parts. Supported byState Key Laboratory of Mechanics and Control of Mechanical Structures. |
PDF Full Text Request