The Investigation Of Energy Dissipation Mechanism About Particle Damping Based On DEM

Particle damping technology is new vibration passive control technology which developed since1990’s in the field of vibration control. It can make use of the structural pre-existing voids or enclosures attached to structure to partially fill with particles.When the structure moves,the particles collide with each other and with the enclosure causing damping through inelastic of nearly collisions, and convert kinetic energy into heat or sound energy. At the same time,the momentum conversion between particles and structure can also suppress the dynamic response of primary system.It enjoys a lot of advantages such as:it can be used in a wide range of environment,the structures are modified hardly,additional mass to the system is minimum,and the effect of vibration absorption is notable etc.All of them make it to be used widely in the future.At present,the researches on particle damping are falling to doing,and the theories are not far away from satisfactory. In this paper,some theoretical model and simulation are introduced to study the dynamic characteristics of particle damping, and some technique are used to control and improve the performance of particle damper.The thesis firstly illustrated the principle of three-dimensional discrete element method and algorithm, and built the NOPD DEM model.Then the model was used to analyze and discuss the factors that influence reducing vibration characteristics. By using the basic principle and DEM calculation method, the matlab simulation program of particle damping was compiled,then we used the program to investigate energy dissipation characteristics about particle damping in some specific circumstances. In the cases of free attenuation and external incentive,we compared the motion of system with and without particles in detail, analyzed the particle damping vibration reduction and energy dissipation mechanism of system. We studied the damping vibration reduction in different filling rate and different particle materials and different particle sizes.In brief,the paper fully considered the complexity of the NOPD damping mechanism,applied the methods of theoretical analysis, numerical simulation and experimental design and experimental study,deeply discussed the vibration reduction mechanism,provided certain theoretical basis and the guiding principle for its engineering application.The result of this paper has important theoretical meaning and engineering value for promoting the application of reducing vibration and noise in low frequency.