【摘要】 模拟了活塞换向撞击、侧压力、曲轴主轴颈负荷单独作用及各激励和燃烧激励共同作用时引起的缸盖表面振动信号,并对各激励振动响应信号的时频特点进行了分析.结果表明,各激励引起的缸盖表面振动位移主要反映了2,kHz以下的低频振动,振动速度和加速度能同时反映系统的低频及高频振动,在时域和频域上各激励振动响应存在耦合.但侧压力及曲轴主轴颈负荷引起的振动信号幅值较燃烧激励引起的振动信号幅值小两个数量级,对燃烧激励振动响应的影响可以忽略;活塞换向撞击对燃烧激励引起的振动位移及振动速度的影响可以忽略,但对燃烧激励引起的振动加速度的影响不能忽略.更多还原

【Abstract】 The vibrations excited individually and coordinately by combustion,piston slap,side pressure and crack shaft main journal load are simulated.Time-frequency analysis of these vibrations is presented.Results show that the vibration displacements mainly reflect the low frequency vibration components less than 2,kHz while the vibration velocity and acceleration reflect both low and high frequency components.The vibrations excited by non-combustion excitations are coupled with the vibrations excited by combustion both in time and frequency domain.The vibration amplitudes excited by side pressure and crack shaft main journal load are much smaller than the vibration amplitude excited by combustion.The influence of side pressure and crack shaft main journal load on combustion vibration response can be ignored.And the influence of piston slap on combustion vibration displacement and vibration velocity can also be ignored but the influence on vibration acceleration can not be ignored.更多还原