抄録
The damping effect of a dynamic vibration absorber (DVA) with granular material in a horizontally vibrating system is studied both experimentally and analytically. Different from the conventional DVA, granular materials are placed into the cavity attached to the absorber mass. The principle behind the damping is the removal of vibratory energy for the absorber mass through losses that occur during impact of granular materials which move freely within the boundaries of the cavity. By using the suitable granular material as a damping element, it is expected to obtain a stable vibration damping effect without being affected by temperature change. Therefore, it can be applied in extreme temperature environments, where most conventional DVA would fail. The behavior of granular material was analyzed using the discrete element method. This method makes it possible to consider the effect of granularity on the damping effect. Granular materials used in the experiment were copper balls and were uniform size. It is shown that it is possible to obtain high damping effect. It is also found that the resonance frequency decreases with increasing the mass ratio. In addition, the validity of analytical model of a DVA with granular materials is examined by comparison with experimental results.
