Proposal of a simple analytical model of the vibration damping device using mass embedded in viscoelastic material and investigation of its damping effect of a beam assuming railway vehicle carbody

The authors have been developing a vibration reduction device called eMDVA (embedded mass dynamic vibration absorber) for reducing elastic vibration of lightweight structures. The eMDVA consists of a mass embedded in a viscoelastic material, and the mass can vibrate freely in all directions. In their former works, the authors developed a finite element (FE) model of the eMDVA. They showed that the vibration characteristics of the eMDVA can be controlled by the size of the embedded mass and the size (depth) of the viscoelastic media. Based on these results, we proposed a simple numerical model consisting of a mass supported by several spring elements that represents the elastic properties of the eMDVA, and we also demonstrated how to set its parameters. In this paper, we also propose a new model that takes into account the damping characteristics of the proposed model and describe how to set its equivalent spring and damping parameters. We then formulate a vibration system in which multiple eMDVAs are applied to a beam-like structure simulating a railway vehicle carbody. This paper explains the analytical model and vibration analysis procedure.