含智能流变材料铝合金夹层板结构的动力学特性研究

通过对一种含电流变液铝合金夹层板智能结构的动力学实验与仿真，分析和研究该结构在外电场作用下的动力特性变化。实验发现，利用外部控制条件(电场强度)的变化，可以改变结构的固有特性，如自然频率、结构阻尼等，可实现对结构的主动控制。数值分析时采用粘弹性材料等效处理方法模拟电流变材料，计算得到的结构振动特性与实验结果吻合较好。实验与仿真计算结果均表明，随着电场强度的增大，结构固有频率也随之出现上升，且增幅与场强有关；同时，电流变材料对结构振动所产生的阻尼效应不仅受外加电场影响，还与外加激励频率有关，响应控制实验结果说明电流变材料对结构在固有频率附近所产生响应的控制效果要更为明显一些。

STUDY ON DYNAMIC CHARACTERISTICS OF ALUMINIUM ALLOY SANDWICH PLATE EMBEDDED WITH ER MATERIAL

The dynamic characteristics of a sandwich plate with two Aluminium alloy plates as its surface layers and electrorheological fluid (ERF) as its core layer are studied numerically and experimentally. It is found that by adjusting the strength of the applied electric field, the inherent characteristics of this composite structure, such as the natural frequencies and the structural damping, could be changed quickly. As one of the most important merits of the composite structures, the adaptive character could help people realize active control conveniently. By means of simulating ER material with equivalent viscoelastic material, the numerical results of the structural characteristics match well with the experimental results. Experimental and numerical results show that positive shifts happen to the structural natural frequencies when the electric field strength increases. It is also found in the experiment that the damping effect of ER material on structural vibration is relative to both the external electric field and the excitation frequencies, furthermore, the restrained influences of ER material on structural dynamic responses are more apparent while excitation frequencies are near structural natural frequencies.