Research On Low Frequency Vibration Control Of Sensitive Components Based On Dynamic Vibration Absorber

Communication equipments have played an irreplaceable role in people’s life.It is very important to ensure that the sensitive components of the communication equipment work properly in vibration environment such as earthquake.Low-frequency vibration such as earthquake has caused great trouble for people for a long time.It’s necessary to suppress low-frequency vibration effectively,especially the vibration at the resonant peak.In this paper,a kind of hybrid damping dynamic vibration absorber is proposed,which has the advantages of simple structure,easy maintenance and high stability.It has good vibration absorption effect under low frequency vibration and has important engineering practical value.The main contents of this paper are as follows,The working principle and design theory of the dynamic vibration absorber are summarized.The optimal cohomology frequency and the optimal damping ratio of the vibration absorber are deduced according to the fixed point design theory.The influence of the parameter change on the vibration reduction effect of the vibration absorber is analyzed by simulation.A hybrid damping dynamic vibration absorber is proposed,and the optimal stiffness design of the absorber is carried out.The damping model of the absorber is established,and the porous fluid damping and friction damping are deduced to solve the dynamic response of the absorber with base excitation.In order to verify vibration reduction performance of the hybrid damping dynamic vibration absorber,the specific parameters of the dynamic vibration absorber are designed and calculated,including specification parameters of spring and piston damping hole.The experimental system of hybrid damping absorber was established.The acceleration transmissibility of the vibration absorber was tested in different media(water and silicone oil)respectively,which was used to measure vibration reduction effect.The results show that hybrid damping dynamic vibration absorber has excellent vibration reduction effect in low frequency vibration.The experimental results are compared with the simulation results to verify the correctness of the kinetic theory model.The vibration control effect of the dynamic vibration absorber for the sensitive components in the communication cabinet is discussed respectively with harmonic vibration excitation and the seismic excitation.For harmonic vibration excitation,the model is simplified as discrete spring mass system,and displacement transmissibility matrix of the system is solved by analytic method.The effect of the dynamic vibration absorber on the vibration suppression of the sensitive components with harmonic excitation is analyzed.And the analytic results are compared with the finite element simulation software calculation results to verify correctness of analytical model.The influence of the quality and stiffness parameters of the cabinet and the installation position of the sensitive components on the vibration response is further discussed.For seismic excitation,the finite element method is used to calculate the transient response of sensitive components.The results show that the dynamic vibration absorber has good effect on the transient response.