传统碰撞阻尼的工作原理大都建立在动量交换、摩擦耗能的范围内,动量交换并没有将振动能量永久地消耗掉,摩擦对于高频振动具有较好的减振效果,而对于低频振动效果较差。为此提出一种以微细颗粒塑性变形将振动能量永久消耗掉的新型的碰撞阻尼,称为带颗粒减振剂碰撞阻尼。分别对在传统单体碰撞阻尼和带颗粒减振剂碰撞阻尼作用下悬臂梁减振效果进行试验研究。试验结果表明:以微细颗粒塑性变形消耗振动能量的带颗粒减振剂碰撞阻尼具有优秀的减振效果,远远超过传统单体碰撞阻尼器。带颗粒减振剂碰撞阻尼在低频振动(低于50Hz)中仍然具有良好减振性能,这是其他碰撞阻尼所缺乏的特性。机械振动多为低频振动,带颗粒减振剂碰撞阻尼具有广阔的应用前景。
Energy dissipation mechanisms of conventional impact damping (CID) are mainly momentum exchange and friction. During impact process a lot of vibration energy cannot be exhausted but reverberated among vibration partners. Besides, CID may produce additional vibration to the system or even amplify the response in lower frequency. To overcome these shortcomings, a new fine particle impact damping (NFPID) which introduces particle plastic deformation into impact damper as an irreversible energy dissipation mechanism is proposed to exhaust vibration energy. Experiments on a cantilevered beam with CID and NFPID are performed respectively. It is concluded that NFPID has excellent ability to absorb vibration energy than conventional impact damping Furthermore, NFPID works well in vibrations under low frequency (lower than 50 Hz), which is absent to CID. NFPID has wide and bright prospect of application because most of mechanical vibrations are in low frequency.