基于磁流变弹性体调频TMD的管道竖向振动控制

Vertical Vibration Control of Pipeline by the Frequency Adjustable Tuned Mass Damper Based on Magnetorheological Elastomer

针对TMD只能对结构的某一阶模态中的较窄频率带宽进行有效控制的问题,设计了一种基于磁流变弹性体的调频TMD。利用短时傅里叶变换识别出结构的基频,通过改变电流大小以改变外加磁场的强度,实现磁流变弹性体刚度的变化,从而调节TMD频率与结构的频率相近。对调频TMD减振改良效果进行了数值模拟,对比其在正弦激励和脉冲激励作用下的结构响应。结果表明,相比于常规TMD,变频TMD能更大幅度地降低模型结构的加速度响应峰值幅度,并且能提高模型结构阻尼比,加快结构振动衰减,达到更好的减振效果。

Pipeline structure is prone to vibration in practical use.Based on the vibration control principle of tuned mass damper(TMD),TMD was applied to the vibration control of pipeline.To solve the problem that TMD can only effectively control the narrow frequency bandwidth in a certain mode of the structure,a frequency Adjustable TMD based on magnetorheological elastomer was designed.The fundamental frequency of the structure was identified by short-time fourier transform,and the stiffness of magnetorheological elastomer was changed by changing the magnitude of the current to change the intensity of the applied magnetic field,so that the frequency of TMD was similar to that of the structure.The improvement effect of frequency adjustable TMD on vibration reduction was numerically simulated,and the structural responses under sinusoidal and impulse excitations were compared.The results show that compared with the traditional TMD,the frequencyadjustable TMD can significantly reduce the peak amplitude of acceleration response of the model structure,improve the damping ratio of the model structure,accelerate the structural vibration attenuation,and achieve better vibration reduction effect.