Vibration Characteristics Analysis And Optimal Design Of Typical Viscoelastic Damping Structures

Plates and shells are typical thin-wall components commonly used in engineering. They are susceptible to vibration and easy to cause damage, so it is necessary to damp vibration of them. Viscoelastic damping material has the characteristic of high damping. The vibration and noise can be controlled in a wide range by pasting viscoelastic damping material on the structures. This method is suitable for vibration suppression of plates and shells. It is meaningful to study vibration characteristics of damping structures that are based on these two typical components. In addition, the optimal design of viscoelastic damping structures can not only save viscoelastic damping material but also improve the damping performance, so optimal design is significant.This paper studies vibration characteristics analysis and optimal design of damping plate structure and damping short cylindrical shell structure. First, the paper introduces the basic characteristics, energy-consuming mechanism and mathematical models of viscoelastic damping material. Loss factor which is one of the performance evaluation indexes is also introduced. Then the modal analysis of constrained damping short cylindrical shell is carried out with ANS YS software. On the basis of modal strain energy method, the paper studies the effects to natural frequency and loss factor of damping structures caused by the factors that include the thickness of viscoelastic layer, the thickness of constrained layer, the position of viscoelastic layer, the coverage rate of viscoelastic layer, constraints and rotating speed. Finally, the paper studies the process and implementation method of topological optimization with genetic algorithm. On the basis of the study, optimal design of free damping plate structure, constrained damping plate structure, free damping short cylindrical shell structure and constrained damping short cylindrical shell structure is carried out and the best structures are obtained. The correctness of the results is verified by comparing the best structures and the general structures.