掺氢比对柴油机掺氢EGR燃烧过程的影响  

Effect of Hydrogen Ratio on Hydrogen Enriched Diesel Engine Combustion Process Combined with EGR

作　　者：刘勇强[1] 左承基[1] 徐天玉[1] 

机构地区：[1]合肥工业大学机械与汽车工程学院,安徽合肥230009

出　　处：《内燃机学报》2013年第1期53-58,共6页Transactions of Csice

基　　金：国家自然科学基金资助项目(50776027)

摘　　要：在一台视窗上置式柴油机可视化试验装置上用高速摄影机记录下油门全开时柴油机掺氢EGR燃烧过程的火焰照片,应用三基色法计算了燃烧温度场,结合示功图和放热率曲线分析了掺氢比对掺氢EGR燃烧过程的影响.结果表明:当EGR率一定时,随着掺氢比的增加,着火时刻呈现提前的趋势,燃烧持续时间发生相应改变;缸内最大爆发压力增加,达到峰值压力的时间提前;放热率峰值增加,放热率曲线整体提前;缸内最高温度和平均温度相应增高.当EGR率较大时,燃料不能充分燃烧,热效率下降,随着掺氢比的增加,燃烧过程随之改善.Flame photos of diesel combustion process of hydrogen enriched diesel engine combined with EGR at full throttle were recorded using a high-speed CCD camera in a visualized window on the cylinder- head. In combination with the pressure indicator diagram and heat release rate, the effect of different hy- drogen ratio on combustion process was analyzed through the temperature field in cylinder calculated by three-primary-color method. Results show that, when EGR rate is constant, as hydrogen ratio increases, ignition timing is advanced, combustion duration is varied, peak value of cylinder pressure and heat release rate are increased, cylinder maximum temperature and average temperature are increased accordingly. Experimental results also indicate that fuel is hard to burn completely and thermal efficiency decreases when EGR rate is large. Combustion process is enhanced with the increase olehvdro^en ratio

关 键 词：柴油机 掺氢 燃烧 温度场 三基色法 

分 类 号：TK421.2[动力工程及工程热物理—动力机械及工程]