磁流变夹层简支梁的有限元分析

智能材料——磁流变液(MRF)的流变特性如粘性、剪切弹性模量等随外加磁场可迅速、可逆变化,MRF可用于复合智能夹层梁板结构。建立了MRF简支夹层梁有限元模型,分别形成每层的单元矩阵,推导了MRF夹层梁的动力学方程,研究了上下面板为铝板条的MRF夹层梁的振动特性,进行了实验验证,计算与实验结果吻合较好:随着外加磁场强度的增加,梁的固有频率和损耗因子均增大,说明磁流变液在外加磁场作用下对夹层梁有显著的抑振作用。

FINITE ELEMENT ANALYSIS OF A SIMPLY SUPPORTED MRF SANDWICH BEAM

The properties of magnetorheological fluid (MRF) materials such as viscosity and shear modulus may vary quickly when the materials are subjected to varying magnetic fields. The MRF materials can be used to make the smart composite structures such as MRF sandwich beams and plates. In the paper, a finite element model of a simply supported MRF sandwich beam has been developed to investigate the vibration characteristics of the MRF sandwich beam structure with a MRF sandwich layer between two elastic aluminum layers. In modeling of the beam, the element matrices of three layers are formed, the dynamic equations are developed. The predicted natural frequencies and energy loss factors of the MRF beam have been validated by a performed experiment, indicating that the finite element results are agree well with the experimental results. The results show that the natural frequencies and energy loss factors of the MRF beam become higher with the increasing of applied magnetic field strength. The vibration of sandwich beam with MRF is of considerable suppression for applied magnetic field.