EGR率对柴油机富氢EGR燃烧过程的影响  

Effect of EGR Ratio on the Combustion Process of Diesel Engine with Hydrogen-enriched EGR

作　　者：左承基[1] 刘勇强[1] 程晓章[1] 徐天玉[1] 吴桐[1] 

机构地区：[1]合肥工业大学机械与汽车工程学院,合肥230009

出　　处：《汽车工程》2013年第3期202-206,201,共6页Automotive Engineering

基　　金：国家自然科学基金项目(50776027)资助

摘　　要：在一台柴油机可视化实验台上,用高速摄像机拍摄下柴油机富氢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EGR率对富氢EGR燃烧过程的影响。结果表明:当掺氢比为2%时,随着EGR率的增加,着火时刻呈现推迟的趋势,燃烧持续时间先延长后缩短;缸内最大爆发压力减小,达到峰值压力的时间推迟;放热率峰值下降,放热率曲线整体推后;缸内最高温度和平均温度随之降低。The flame photos in the combustion process of diesel engine with hydrogen-enriched EGR are taken by the high-speed video camera of a visualization unit attached on the diesel engine test bench and are then processed with three primary color method to calculate the temperature field in cylinder, and the effects of EGR ratio on combustion process are analyzed with the combination of indicator diagram and heat release rate curve. The resuits show that in a Condition with a hydrogen blending ratio of 2%, as the EGR ratio increases, the ignition delays, the combustion duration extends first and then shortens, the peak explosion pressure lowers with its timing retards, the peak heat release rate drops, the whole curve of heat release rate shifts to the right and both the peak and average in-cylinder temperatures lower accordingly.

关 键 词：柴油机 富氢EGR 燃烧 温度场 三基色法 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]