Papers by Keyword: Impact Damper

Abstract: The activated carbon fine particles, as damping agents, are filled into the impact damper. With experimental method, the performance of the fine particles impact damper to the main system is compared with the multi-unit impact damper. The results indicate that the damping effect of the impact damper with activated carbon fine particles is not better than that of the multi-unit impact damper, but it has a much better effect to restrain the strong nonlinear of response than the multi-unit impact damper. In a certain resonance region, there is an optimum particle filled rate to the fine impact damper.

Abstract: We present a simulating experimental method used for studying the influence of impact mass on damping performance of impact dampers. The free mass in the impact damper had equal total mass but different size individual. We tested the damping effect of the damper under the same external force separately. The main results obtained in the experiments indicated that the impact damper had a good damping effect in the resonance region of the main system. The mass value of the free mass participating in vibro-impact was variable. In addition, the damping of the main system was related to the size of the free mass. In the conditions of equal total mass and same material, the size of the free mass was smaller, the effect of the vibration control was better.

Abstract: This paper studies the effect of damper components on the performance of the impact damper with fine particles as damping agent (IDFPDA). The responses of various damper combinations are obtained from the experiments of a cantilevered beam attached by the IDFPDA with different impactor diameter and particle material. Results show that the average attenuation rate is 72.7~75.4% by changing the particle material in IDFPDA and the average attenuation rate is 72.1~75.9% by changing the diameter of impactors, which are much higher than that without particles or impactors. The conclusions can be drawn that the IDFPDA has more excellent performance than traditional impact damper only with impactors or particles. The impactor diameters and the particle materials have little effect on the damping performance, so both metal and non-metal particles are suitable to IDFPDA.

Abstract: We present a simple mathematical model of a wind turbine supporting tower. Here, the wind excitation is considered to be a non-ideal power source. In such a consideration, there is interaction between the energy supply and the motion of the supporting structure. If power is not enough, the rotation of the generator may get stuck at a resonance frequency of the structure. This is a manifestation of the so-called Sommerfeld Effect. In this model, at first, only two degrees of freedom are considered, the horizontal motion of the upper tip of the tower, in the transverse direction to the wind, and the generator rotation. Next, we add another degree of freedom, the motion of a free rolling mass inside a chamber. Its impact with the walls of the chamber provides control of both the amplitude of the tower vibration and the width of the band of frequencies in which the Sommerfeld effect occur. Some numerical simulations are performed using the equations of motion of the models obtained via a Lagrangian approach.