ER Fluid Application to a Controllable Mount

本课题研究了一种半主动基础隔震系统，该系统采用阻尼可控隔振器。阻尼可控性是通过将电流变（ER）流体施加到隔振器上来实现的。电流变液是一种高性能材料，其表观粘度可以随外加电场的变化而变化。电流变液具有表观粘度变化范围宽、响应时间快等优点.与没有任何电场时所获得的值相比，当受到一些电场时，粘度可以变化数十倍或数百倍。该隔振器的响应时间可短至几毫秒。在恒定振幅的条件下进行了实验，详细研究了电流变阻尼器对小振幅振动的阻尼效率。研究结果表明：（1）通过控制外加电场强度，可以改变隔振器的刚度和阻尼。(2)提出了一种理想化的隔振器模型。(3)阻尼可控性被证明是依赖于振动振幅。

In this project, one kind of semi-active base isolation system is dealt with, in which a damping-controllable vibration isolator is adopted. The damping-controllability was accomplished by applying Electro-Rheological (ER) fluid to the isolator. ER fluid is known as a class of highly functional material whose apparent viscosity can be varied in response to the applied electric field. The attractive characteristics of ER fluid are wide variation of apparent viscosity and quick response time. The viscosity can be varied several tens times or hundreds times compared with the value obtained without any electric field when subjected to some electric field. The response time is said to be as short as several milliseconds.A prototype vibration isolator was constructed and its performance was investigated. The experiments were conducted under the condition of constant vibration amplitude, in which a detailed investigation was made into the efficiency of ER damper for a small amplitude vibration. Conclusions obtained are as follows ; (1) Stiffness as well as damping capacity of the present vibration isolator can be varied by controlling the applied electric field strength. (2) An idealized model was proposed for the present type of vibration isolator. (3) The damping controllability was shown to be dependent on the vibration amplitude.