Study on Piston Slap Induced Liner Cavitation
Study on Piston Slap Induced Liner Cavitation
复制标题
DOI：
10.1115/1.4030360
复制
发表时间：
2015-10
期刊：
影响因子：
--
通讯作者：
Xiao Yu Wang;K. Ohta
中科院分区：
文献类型：
--
作者：
Xiao Yu Wang;K. Ohta
柴油机活塞拍击缸套穴蚀是由于冷却液压力低于饱和蒸汽压时的水压波动引起的。缸套的空蚀是由空泡溃灭后的冲击压力或射流冲击产生的。本文提出了一种预测活塞撞击力引起的冷却水通道内水压力波动的数值方法。在往复冲击振动实验中，当压力达到饱和蒸汽压以下时，可以观察到水压波动的高频成分，这些高频成分似乎表明了空化现象的发生。建立了实际发动机缸体冷却水通道的有限元声学模型，并通过空气中的声振试验验证了模型的正确性。在此基础上，确定了水声场与机体结构的耦合振动特性，预测了活塞拍击引起的水压力波形。
Liner cavitation induced by piston slap in a diesel engine is caused by water pressure fluctuation when the pressure of coolant falls below saturated vapor pressure. Cavitation erosion of cylinder liners is thought to be generated by the impulsive pressure or jet flow impingement following the collapse of cavitation bubbles. In this study, a numerical method to predict the water pressure fluctuation in water coolant passage induced by piston slap impact force is developed. In complimentary impact vibration experiments, high frequency components of the water pressure fluctuation can be seen just after the pressure reaches the saturated vapor pressure level or less. These high frequency components seem to show the occurrence of cavitation. A finite element acoustic model of the water coolant passage in an actual engine block is created and its validity is confirmed by the acoustic vibration tests in air. Then, the coupled vibration characteristics of the water acoustic field and engine block structure are determined, and water pressure waveform induced by piston slap is predicted.