Application Of Restoring Force Surface Method In Particle Damping Research

The particle damping is a passive technique of vibration control. To further understanding its complex nonlinear dynamic behavior and mechanism of energy dissipation, this paper applies the restoring force surface (RFS) method to estimate the parameters of the particle damping system. And this is the first time to use the RFS method for the particle damping systems.To apply the RFS method to identifying parameters of the particle damping systems, acceleration terms are added into the restoring force equation. Then the modified RFM is utilized to the equivalent damping ratio of a particle damped cantilever beam system, the results show that the modified one is more accurate than the conventional one.There are many factors that can influence the equivalent damping ratio of a particle damping. In this paper, by altering the diameter of the particles, mass of the fillings, filling ratio, and vibration level, the relationships between the equivalent damping ratio and those parameters are established. The results show: a) When the filling ratio falls into the range of 50% and 80%, the equivalent damping ratio increases firstly as force level is increased, and then decreases as force level increased. But when the filling ratio reaches 90%, the equivalent damping ratio always increases with the vibration level. b) The equivalent damping ratio increases as the mass of filled particles increases. c) The smaller the particle is, the better performance it will be. d) The equivalent mass decreases as force level is increased.The RFS method is successfully applied to the parameter identification of the particle damping systems. The results are reliable and show that RFS method is a useful tool for the estimation of particle damping properties.