机械改液压挺柱的应用及其对噪声的影响

Application of Mechanical Tappet Converted to Hydraulic Tappet and Influence on Noise

在一款成熟的国六柴油机上,将原机械挺柱改为液压挺柱,在尽量不改变目前整机结构的情况下进行布置,并设计了新的凸轮型线拟合原气门升程,验证机械挺柱改液压挺柱对柴油机NVH性能的影响。试验表明,应用液压挺柱可实现全转速工况内发动机顶部降噪0.6~3.2 dB。发动机在转速低于1600 r/min时,5点平均噪声降低0.5~1.2 dB,但在较高转速时,发动机整体降噪效果不明显。

On a mature National VI diesel engine,the original mechanical tappet is changed to hydraulic tappet,and the layout is made without changing the current overall structure as much as possible,and a new cam profile is designed to fit the original valve lift,verify the impact of changing mechanical tappets to hydraulic tappets for diesel engine NVH performance.Tests show that the application of hydraulic tappets can reduce noise on the top of the engine by 0.6~3.2 dB at all speed.When the engine is lower than1600 r/min,the five working conditions point average noise is reduced by 0.5~1.2 dB,but at higher speeds,the overall noise reduction effect of the engine is not obvious.