Research On Nano-MR Damper And Its Application

Because there are high yield stress, high reflect speed rate, low energy consumption, small pollution effect, etc., MR (magnetorheological ) becomes first choice for damper material. Principle of tradition damper is that change damper force with damper channel adjustment. There are the defects of complex construct and long reflect time on tradition damper. The principle of MR damper is change damper force by modifying fluid nature. It develops a new idea for damper and has significant research value and application prospect.Based on present development of high speed elevator and MR material technique , MR damper techniques have systemically studied on the dissertation. It includes mechanism of magnetorheology, nature of MR, theory of MR damper, design method, damper experiment, and vibration control of high speed elevator. All of those in order to promote development of MR damper and high speed elevator reducer technique. The main content of each chapter is as following.The first chapter according to large sums of documentation and information, overview the development of MR, MR damper, high speed elevator. Represent important and necessary of research to MR damper and vibration damp system of high speed elevator. Main content of the project is determined as MR damper and vibration damp system of high speed elevator.The second chapter introduces MR phenomenon, MR mechanics, MR fabric, theoretically analyses stability of MR. Relative experiments have done. In order to understand nature of MR. Some researches are done, such as analysis of paramagnetic phenomenon and paramagnetic relaxation, influence of volume percent to viscosity. Finally the project finished viscosity-temperature and nature of MR. All of those lay foundation of research on MR damper.Main study is magnetic field problem in the third chapter. The dissertation studies magnetic field of MR damper's coil, then discusses the problems ofelectromagnetics in MR damper design. The paper deduces formula of magnetic circle and electric circle of MR damper and certified those through experiment.According to the model of MR damper, these mechanical modes are built in the fourth chapter. The project discussed influence of damp force to the parameter of MR damper and carried finite element analysis of MR flow field and shearing stress. These works established the study foundation of MR damper.In the fifth chapter, the dissertation designed the MR damper for elevator through analysis of structure and character of MR damper. On basis of experience of practice deign, the paper put forward a design guide rule of MR damper.On the basis analysis on diagram of work and speed character of damper, the dissertation narrated the important of the natures in the sixth chapter. A series of experiments have done. Those include demonstration one, diagram of work experiment, speed character experiment of damper, acceleration experiment, and reflection experiment. The experiments gained the character of MR damper, proved that MR coincides Bingham model constitutive equation and reflection time of MR damper can reach microseconds.After introducing development of elevator amenity, the seventh chapter discussed elevator amenity standards and considered that lateral direction vibration is one of main aspect on elevator amenity. Based on analysis of elevator vibration, elevator vibration control has done by relay method, modified relay policy and fuzzy variable structure strategy. The experiment indicates the result by fuzzy variable structure strategy control is best. The research shows that Nano-MR damper as elevator vibration reducer is success.The eighth summarizes the main achievements and innovation points of the project, and prospects the demand research work needed for the future.Summarizing the dissertation, project study characters of Nano-MR and the damper put forward the criterion based on nanometer technology function material, electromagnetism, rheology, mechanics aspects. Finally the project design lateral vibration reducer of high speed elevator. These fill-up the blank.