Design And Research Of Eddy Current Damping Dynamic Vibration Absorber

In this paper,the dynamic vibration absorber with eddy current damper was simulated,designed and manufactured.The influence of various parameters of eddy current damper on its damping force was explored.On this basis,a variable damping dynamic vibration absorber with eddy current damper was designed.The dynamic characteristics under different damping values were studied thought the experiment method.First of all,the fixed-point theory of dynamic absorber and the optimal parameters design were deduced,and the influence of mass,damping ratio and natural frequency of dynamic absorber on the vibration absorption effect were discussed.The parameters of dynamic absorber were designed,so that the vibration absorption effect could reach 5dB in a certain bandwidth.Then,the molecular current method was used to deduce spatial distribution of magnetic field of cylindrical permanent magnet.The Comsol of finite element software was used to simulate spatial distribution of magnetic induction intensity of cylindrical permanent magnet.The simulation results were compared with the theoretical calculation to ensure the accuracy of simulation analysis.The influence of the thickness of ferromagnet and the distance from permanent magnet on the spatial distribution of magnetic induction intensity of permanent magnet were simulated and analyzed.Next,the principle of eddy current damping was introduced briefly.The formula of eddy current damping force on a conducting plate moving in an arbitrary magnetic field was deduced theoretically.On this basis,the formulas were programmed into the finite element software Comsol to simulate the damping force of the metal plate moving in the magnetic field generated by the cylindrical permanent magnet,and the single pendulum experiment was used to calculate the eddy current damping force of the aluminum plate moving relative to the cylindrical permanent magnet.The effects of the thickness of the conductor plate,the distance between the conductor plate and the surface of the permanent magnet,the distribution of the permanent magnet and the magnetic conducting plate on the eddy current damping force were simulated.Finally,a dynamic vibration absorber with eddy current damper was designed.Adjusting eddy current damping device,the means of constant acceleration sweeping frequency method and single frequency excitation were used to obtain the natural frequencies,the effect of vibration absorption and the damping ratio of the dynamic absorber under different working conditions.By comparing the eddy current damping force calculated via the experiments under different working conditions with the simulation results,the reliability and feasibility of the eddy current adjustable damping dynamic absorber designed in this paper were verified.