圆盘式磁流变调速风扇离合器的理论研究

应用B ingham模型来描述磁流变液的本构方程,在理论上分析了盘式磁流变液风扇离合器的调速机理;建立了离合器传递转矩与输出转速的计算模型,并导出了设计计算公式;讨论了动态响应特性、功率损失特性、传递的转矩及调速范围与离合器结构参数等因素的关系。结果表明:影响离合器动态品质的主要因素为其结构参数,减小从动盘的转动惯量可以改善系统的动态特性;离合器的调速范围主要由工作间隙和磁流变液零场粘度决定,减小磁流变液零场粘度和适当增大工作间隙可以减小粘性功率损失,提高效率。

Theoretical Analysis of a Disc-shaped Magnetorheological Fan Clutch

A Bingham model was used to characterize the constitutive behavior of magnetorheological(MR) fluids subject to an external magnetic field.The model of the torque and the output rotational speed within the clutch was set up and the expressions for the design of clutch were derived.Based on these equations,the calculations of the radius of the disc,the thickness and volume of MR fluids within the MR fluid clutch were yielded.The results show that geometric parameters of MR clutch are the main factors which affect its dynamic performance,and the dynamic properties are improved as moment of inertia of the passive plate decreases.The range of speed regulation depends on the working gap and initial fluid viscosity.The viscous power loss decreases as the working gap increases or initial fluid viscosity decreases.