摘要
通过一台由多缸柴油机改造的单缸重型发动机,研究了喷油时刻(SOI)、喷油压力和点火时刻(ST)对火花辅助汽油压燃(SAGCI)低负荷燃烧的影响.结果表明:喷油时刻与点火时刻合理配合对保证燃烧稳定性非常关键,在低负荷工况条件下,喷油时刻需在-34°~-20°CAATDC的范围内才能保证混合气被点燃,而点火时刻与喷油时刻控制为2°~18°CA的间隔才能保持良好的燃烧稳定性;提高喷油压力可以拓宽稳定燃烧的喷油和点火时刻范围,同时可以加速火焰传播过程,提高该边界下的指示热效率(ITE).在循环油量为33 mg下采用80 MPa喷油压力,此时CoV;=1.3%、压力升高率为0.2 MPa/(°)CA,火花辅助压燃燃烧效率达到96.7%,指示热效率为33.89%.
An experiment was carried out on a single-cylinder heavy-duty testing engine modified from a multicylinder diesel engine to study the effect of start of injection(SOI),fuel injection pressure,and spark timing(ST)on spark-assisted gasoline compression ignition(SAGCI)for low-load operating conditions.Results show that the coordination of SOI and spark timing is critical for combustion stability.The SOI should be controlled within the range of-34°to-20°,CA ATDC to ignite the air-fuel mixture,and the interval of the spark timing and the SOI should be controlled between 2°—18°,CA to guarantee combustion stability.Increasing the fuel injection pressure helps to extend the span of SOI and spark timing for stable combustion,accelerate flame propagation,and improve the indicated thermal efficiency(ITE)under this condition.When adopting a fuel injection pressure of 80 MPa with a fuel consumption of 33 mg per cycle,the ITE of 33.89%and combustion efficiency of 96.7%can be achieved under the CoV;of 1.3%and the pressure rise rate of 0.2 MPa/(°),CA.
作者
李扬
郑尊清
陈鹏
王梦凯
王浒
尧命发
Li Yang;Zheng Zunqing;Chen Peng;Wang Mengkai;Wang Hu;Yao Mingfa(State Key Laboratory of Engines,Tianjin University,Tianjin 300350,China)
出处
《内燃机学报》
EI
CAS
CSCD
北大核心
2022年第4期289-296,共8页
Transactions of Csice
基金
国家自然科学基金资助项目(51976134).
关键词
重型发动机
火花辅助汽油压燃
低负荷
喷油策略
点火策略
燃烧稳定性
heavy-duty engine
spark-assisted gasoline compression ignition(SAGCI)
low-load conditions
fuel injection strategy
ignition strategy
combustion stability
