摘要
内燃机燃烧过程中,高温高压的混合气体与燃烧室构成的空腔为缸内气体声学振荡提供了条件,这种振荡现象与燃烧噪声的产生直接相关,属于强非稳态的非线性范畴。由于这些振荡受到很多因素影响,其复杂性导致至今仍无一个实时计算的手段。为研究燃烧过程中压力波动产生的机理,由KIVA燃烧计算的流场模型推出三维声学波动方程,并与KIVA源程序相结合求解。由于汽油机爆震时这种声学振荡最为明显,利用所得方程对某一工作与爆震工况下的汽油机进行计算,得出了爆震燃烧过程中声学振荡的过程及声学激励项的特征。分析各声源随曲轴转角变化的曲线,得出各燃烧激励源对气缸压力波动的贡献及声场分布情况;同时,对比与计算相同工况下试验获取的气缸压力振荡数据,讨论了燃烧室声学振荡规律。
In IC engine combustion,mixture with high temperature and pressure is apt to oscillate in the cavity of combustion chamber.The oscillations in cylinder,which is directly correlated with combustion noise, belong to the intensive unsteady nonlinear category.As this kind of wave is influenced by many factors,there is still not an effective method to simulate the complex combustion noise.To investigate mechanism of the origination of pressure oscillations in combustion,a three-dimensional wave equation is derived from the control equation set of KIVA.The wave equation is embedded in KIVA source code and solved during the calculation of combustion with the source items obtained from main KIVA program.Generally,the acoustic oscillation is remarkable when engine is knocking.By applying the wave equation to engine is under knocking condition,the pressure oscillations and the characteristics of those stimulated items are obtained.Contributions of the source items to the acoustic oscillations are discussed by analyzing the calculated results.The regulation of acoustic oscillations in cylinder is identified when comparing the acquisition data with engine experiments.
出处
《内燃机学报》
EI
CAS
CSCD
北大核心
2010年第5期427-434,共8页
Transactions of Csice
基金
国家自然科学基金资助项目(50706032
50476065)
教育部博士点基金资助项目(20040056023)
关键词
燃烧
振荡
声压
激励
爆震
Combustion
Oscillation
Acoustic pressure
Stimulation
Knock
作者简介
作者简介：韦静思，博士研究生，E—mail：ningju@163．com。
通讯作者：卫海桥，副教授，E-mail：whq@tju．edu．cn。
