摘要
对机载仪器设备进行振动控制是提高其精度和寿命的重要手段。发动机、其它设备或者外部环境振动通过机体结构传递到机载设备。从这一实际出发,将机体结构建模为弹性梁,认为外部激励直接作用于梁结构,并通过隔振器传递到机载设备。运用子结构导纳法建立基础-隔振器-刚体系统动力学模型,推导出由基础结构通过隔振器传递到机器设备的速度传递率表达式,分析速度传递率随激励频率和激励施加位置变化规律,并通过试验进行验证。结果表明,基础梁的横向共振是导致传递率增大的主要原因;相对于基础梁非对称激励能激发更多基础结构弯曲共振模态;高频激励会引起隔振器纵向与弯曲共振产生驻波效应;推导出公式在100 Hz^1 000 Hz之间能够比较准确地反映传递率的变化。
It is important for devices and equipment on board to isolate the vibration from base structures because of the dependency of accuracy and lifespan of the equipment on the vibration. The excitation comes from the base structure directly to the devices, so a dynamic system that consists of a flexible base, vibration isolators and a rigid body needs to be considered. In this paper, the model of the dynamic system including devices and equipment on a flexible base structure was constructed based on sub-structure method and the concept of admittance. The expression of vibration transmission rate from the base to the equipment was deduced. The effects of frequency and allocation on the vibration transmission rate were analyzed by simulation and tests. The result shows that the transverse resonance of the beam in the base structure is the main reason of the high vibration transmission rate;the non-symmetrical excitation can arouse more bending resonant modes of the infrastructure;the higher frequency excitation can cause the resonance of the longitudinal and bending vibrations which can result in stationary wave effect; the given expressions can reflect the vibration transmissibility accurately in the frequency range of 100 Hz-1 000 Hz.
出处
《噪声与振动控制》
CSCD
2016年第2期139-143,共5页
Noise and Vibration Control
基金
山东省优秀中青年科学家科研奖励基金资助项目(BS2010ZZ010)
关键词
振动与波
传递率
被动隔振
柔性结构
vibration and wave
transmission ratio
passive vibration isolation
flexible structure
