Research On Theory And Pivotal Technology Of Megnetorheological Controllable Damping

A new damping technology-- magnetorheological (MR) fluid controllable damper is to use the MR fluid as medium in a damper and to control its damping characteristics by extern-magnetic field. Therefore, the property of the damper depends on magnetic-magnetic field parameters and magnetic-viscosity characteristics of the MR fluid. In this paper, the effect of various parameters on damping force has been discussed by analyzing of the damping mechanism. Especially, the theory and method to realize the damping control were emphasized.The damping mechanisms, the conditions of damping forming, factors of realizing damping control and how to realize the control by adjusting fluid viscosity were respectively discussed in the paper. The operating case of current liquid dampers, in which have been used in engineering, has been investigated by analyzing the distribution of oil kinetics parameters such as pressures and flow velocities based on finite element method (FEM) for design of constructer of the new MR fluid damper and its characteristic simulation.Based on viscous fluid dynamics and vibration absorbing theory, a new partitioned space discrete analogy has been put forward and its damping characteristics simulating model have been developed by dealing with some crucial technical problems and coupling oil physics properties and surroundings parameters such as temperatures and pressures. The effects of all kinds of damping factors on work display chart of damper and its damping characteristics were also analyzed by using model above.A new MR damper test machine and its data processing system were developed for researching the effect of control parameters on damping characteristics and obtaining experimental data. The test results shown that consistent between the theoretical and the experimental data and simulating model's reliability as well its usability in engineering was confirmed.In the dissertation, the dynamics properties of MR fluid and the relationship between its viscosity and extern-controllable magnetic field were investigated. Furthermore, the magnetic-viscosity characteristic of MR fluid in given condition wasmeasured and the correlation between MR fluid viscosity and magnetic field intensity can be established.The extern-magnetic field control mode and damp processing mode were researched by the FM model and numerical simulating analysis. The matching for different materials in damper magnetic loop and damping characteristics were also investigated. A new MR damper sample was developed based on deal with for some pivotal technical problem of the damper design. Experimental results verify that the new MR damper has better controllable characteristics.It is possible that the theoretical and experimental results above can provide valuable reference for the further application in the area of engineering.