摘要
研究单活塞液压自由活塞发动机原理样机活塞组件振动特性.建立活塞组件动力学模型,导出了活塞振动方程,研究了活塞的幅频特性并运用相平面法分析了活塞运动的稳定性.活塞组件运动属于单自由度变阻尼、变刚度自振振动.活塞运动频率与振幅间存在单调上升关系且受压缩比的限制,其稳定极限环存在的区域由进气口位置和活塞行程决定,下止点位置位于稳定极限环存在区域是实现自激振动的关键,工作频率可以在零和自激振动频率之间调整.
Piston oscillation characteristics of a single piston hydraulic free-piston engine prototype are studied. Dynamical model of the piston assembly is built up and the oscillation of motion deduced. The amplitude-frequency characteristic is given and the stability of the piston motion is analyzed by the phase plane method. The piston motion is a kind of single-degree-of- freedom, variational damping and stiffness autooscillation oscilation. The piston vibration frequency has a monotonous increasing relationship with the amplitude and is limited by the compression ratio. The stable limit cycle area is determined by the position of air intake and the throw of piston. The realizing of self-excited vibration is confirmed by BDC＇s position lied in the stable limit cycle area. The assigned frequency can be regulated from zero to the self-excited vibration frequency.
出处
《北京理工大学学报》
EI
CAS
CSCD
北大核心
2009年第4期304-308,共5页
Transactions of Beijing Institute of Technology
基金
国家部委基础科研项目
关键词
自由活塞发动机
振动特性
稳定性
液压系统
free-piston engines
oscillation characteristic
stability
hydraulic system
