【摘要】 设计了5种进气道热碰壁制备柴油均质预混合气的油嘴方案,根据燃油吸入比例、NOx排放和排气不透光度,对喷孔数量、油束着壁入射角度α(油束轴线与壁面法线的夹角)进行了优化研究。结果表明,当α=15°时,喷孔数量增加会使高壁面温度时排气不透光度降低,但不能有效提高燃油吸入比例,而当α=45°时,喷孔数量增加对排气不透光度影响很小,却有利于提高燃油吸入比例。对不同的α,喷孔数量增加都会减少NOx排放。随α减小,燃油吸入比例逐渐升高,但从NOx排放和排气不透光度分析,存在最佳α值。综合分析认为,对本文试验组,喷孔数量选择6个,α选择30°为最佳方案。更多还原

【Abstract】 Based on the sucked fuel ratio,NO_x emission and exhaust opacity,the nozzle hole number and the angle of incidence(the angle between the nozzle hole axis and the wall normal) α were optimized through comparison of 5 kinds of nozzles for premixed diesel homogeneous charge preparation by spray hot-impingement at intake manifold.Results show that,if α=15°,to increase the hole number would reduce the exhaust opacity,but could not effectively increase the sucked fuel ratio.But when α=45°,to increase the hole number would effectively increase the sucked fuel ratio,whereas could not reduce the exhaust opacity.The NO_x emission would decrease when hole number increased.If α decreased,the sucked fuel ratio could be enhanced.There is a best α for NO_x emission and exhaust opacity.For the 5 nozzles,the nozzle with 6 holes and α=30° is the optimized case.更多还原