基于磁场FE和CFD的磁流变阻尼器力学性能分析

针对某重型机械中安装的双出杆双线圈可复位式磁流变阻尼器，利用实验和仿真方法对其在特定冲击作用下的力学性能进行分析。利用磁场有限元(FE)和计算流体动力学(CFD)的单向耦合数值模拟方法，建立含隐式动网格边界的阻尼器数值模型，通过准静态实验对模型进行了验证。利用基于C语言的用户自定义函数(UDF)定义磁流变液体的本构模型，捕获磁场作用区域。结果表明，在持续通电的情况下，受到冲击后，阻尼器速度在80ms内降至零，但活塞在复位过程中停在位移为1.3mm处，控制电源断开后能够使其完全复位。

Mechanical Performance Analysis of MR Damper Based on Magnetic Field FE and CFD

Magnetorheological (MR) damper is widely used due to its excellent damping and controllability. A resettable magnetorheological damper with double-ended and double coils was installed in a heavy machinery. In order to study the mechanical performance of the damper under a specific impact, experimental and simulation methods were used for analysis. Through the one-way coupling numerical simulation method of magnetic field finite element (FE) and computational fluid dynamics (CFD), a numerical model with implicit dynamic mesh boundaries was established in ANSYS/Fluent based on six DOF module. A user-defined function (UDF) based on C language was used to define the constitutive model of MR fluid and capture the magnetic field. The model considered the non-Newtonian region overflowing on both sides of annular gap, the compressibility of liquid and the polytropic process of air spring. In addition, the CFD model was verified by a uniform quasi-static experiment. The results showed that under the condition of continuous power-on, the damper velocity after impact was dropped to zero within 80ms, but the piston was stopped at a displacement of 1.3mm during the reset process, and the power can be completely reset after being disconnected. During the impact, a number of different vortices were generated in the fluid domain, and the larger vortices appeared on the back side of the piston movement direction. The heat that caused temperature rise was mainly generated in the annular gap, and the temperature distribution in fluid domain was uneven. The research mainly provided research methods and theoretical support for MR dampers under impact.