关键词: 压电分支阻尼;叶盘结构;振动抑制;机电耦合系数;拓扑优化

Abstract: This study concerns the application of piezoelectric shunt damping in the vibration reduction of the bladed disks in aero-engines. A topology optimization method for the distribution of the piezoelectric materials on the disk of a blisk modal is proposed. The method enables the maximum damping with a restricted amount of piezoelectric materials. Moreover, bonding the piezoelectric materials on the disk prevents the interference to the fluid field and therefore it preserves the fluid efficiency. First, the theoretical basis of the topology optimization is introduced. The modal electromechanical coupling coefficient (MEMCF) is the critical parameter relating the modal strain field, the modal frequency and the best damping ratio. Its calculation formula is derived. Second, the topology optimization is proposed based on the modal strain field. Note that this method is applicable to arbitrary structures once the finite element models are given. Eventually, the proposed method is applied in a compressor bladed disk of aeroengine, where both the single-mode and multi-mode situations are considered, to study its effects on the damping in different modes(disk dominant, blade dominant and disk-blade coupled modes). When the mass of piezoelectric materials is only 5% of the disk, the optimized piezoelectric damper can provide up to 13% modal damping ratio for the disk dominant and disk-blade coupled modes. On the other hand, modal damping ratio achieved for the blade dominant modes focuses on 2%~4%.

Key words: Piezoelectric shunt damping;Bladed disk;Vibration reduction;Modal electromechanical coupling coefficient (MEMCF);Topology optimization