多带隙局域共振单元抑振设计与实验验证

Structure design and experimental verification of multi-bandgap locally resonant unit

为拓宽抑振作用频段,提出了一种具有多带隙特性的抑振结构。根据多带隙抑振结构特点,论文推导了其机械阻抗理论公式,建立了两端弹性支撑多带隙局域共振梁动力学耦合模型,基于该模型可完成自由边界、固支边界及一般弹性边界下的结构动力学特性分析。论文以弯曲振动梁为控制对象,完成了多带隙抑振结构优化设计,并在两端自由弯曲振动梁上开展了实验验证工作,实验结果与理论计算一致性良好。研究表明:提出的多带隙抑振结构具有作用频带宽、频率下限低的特点,可为低频振动噪声控制提供参考。

To broaden the frequency range of vibration suppression,a vibration suppressor with multi-bandgap properties is proposed.According to the characteristics of multi-bandgap suppressor,the mechanical impedance equation is derived,and the dynamic coupling model of multi-bandgap locally resonant beam with elastic support at both ends is built.Based on this model,the dynamic properties of the beam under free boundary condition,clamped boundary condition,or other general elastic boundary conditions can be analyzed.The design of multi-bandgap vibration suppressor is carried out by setting the bending beam as the control object.Furthermore,the bending beam with elastic support at both sides under free boundary condition is tested,and the experimental results are consistent with the theoretical ones.The research shows that the multi-bandgap vibration suppressor proposed in this paper has wider frequency range of vibration suppression and lower limit of frequency.It provides references for low-frequency vibration and noise control.