圆盘式磁流变传动机构的研究

本文研究圆盘式磁流变传动机构主要结构参数的设计,它涉及装置的动态品质、磁流变流体的物理性能和机构运行条件。讨论传动机构传递的力矩、动态品质、调速范围、粘性功率损失、传动系统刚度、转速差-磁场强度系数等,它们与圆盘内外半径、间隙、剪切速率、外加磁场强度、MRF的零磁场粘度和屈服应力有关。

基于制动性能的盘式磁流变制动器磁场结构设计及优化

目前常见提升MRB制动力矩的思路主要有提高磁流变液性能、改进制动器结构和增大磁场强度3个方面。目前制备的MRB样机虽然通过改变制动器结构提高了制动力矩,但还存在磁场未能充分利用的情况。通过理论分析、数值模拟和实验验证相结合的手法对线圈外置式和线圈旁置式MRB的制动性能进行对比分析,总结出线圈放置方式对MRB性能的影响规律,为MRB的发展提供参考。

基于CBFM的微带天线阵列电磁特性分析

针对传统矩量法分析电大目标难度大的问题,近几年提出一种有效的方法——特征基函数法。文中采用此方法结合空域格林函数法对一些微带天线阵列的电磁特性进行了研究,其中研究并运用磁流圆盘来模拟同轴激励源,运用简化附加模模型模拟线面连接处的电流。数值分析结果与MOM、软件仿真、相关文献的结果吻合良好,与MOM相比计算时间大大减少,从而证明了此方法的正确性、通用性和优越性。

A disc-type magneto-rheologic fluid damper

A disc-type magneto-rheological fluid damper operating in shear mode is proposed in this paper,which is based on the special characteristics of the magneto-rheological (MR) fluid with rapid, reversible and dramatic change in its rheological properties by the application of an external magnetic field. The magneticfield of the disc-type MR fluid damper is analysed by the finite element method ; the controllability of the disctype MR fluid damper on the dynamic behaviour of a rotor system ; and the effectiveness of the disc-type MR fluid damper in controlling the vibration of a rotor system, are studied in a flexible rotor system with an over-hung disc. It is shown that the magnetic flux density of the disc-type MR fluid damper in the working areas can significantly change with the applied current in the coil ; and that the dynamic behavior of the disc-type MR fluid damper can be varied by the application of an external magnetic field produced by a low voltage electromagnetic coil. The disc-type MR fluid damper can significantly change the dynamic characteristics of a rotor system, provided that the location of the disk-type MR fluid damper is carefully chosen. The disc-type MR fluid damper is a new actuator with good dynamic characteristics for rotating machinery.