正庚烷均质压燃过程的燃烧稳定性和循环变动的研究  

Study of Combustion Stabilities and Cycle-to-Cycle Variations of n-Heptane Homogenous Charge Combustion Ignition(HCCI) Combustion

作　　者：吕兴才[1] 吉丽斌[1] 马骏骏[1] 黄震[1] 

机构地区：[1]上海交通大学内燃机研究所,上海200030

出　　处：《内燃机工程》2007年第6期1-6,共6页Chinese Internal Combustion Engine Engineering

基　　金：上海市自然基金资助项目(06ZR14045);上海市重大基础研究项目(05DJ14002)

摘　　要：对正庚烷HCCI燃烧典型工况下的燃烧稳定性和循环变动进行了研究。在单缸HCCI发动机上,通过气口喷射正庚烷,记录了部分燃烧、正常燃烧、爆震燃烧下100个循环的示功图,据此对各个燃烧参数和性能参数的循环变动进行了分析。研究表明:低温阶段的冷焰反应时刻、起始反应温度和低温放热峰值时刻的循环变动系数小于3%,且受混合气浓度的影响不明显;高温阶段燃烧参数循环变动较大,但是着火时刻和峰值放热时刻随混合气浓度的增加显著减小;低温和高温峰值放热率循环变动系数较高。在性能参数方面:不发生爆震燃烧时,最高压力、压力升高率的变动较小;发生爆震燃烧时,循环变动系数迅速增加;不发生失火或者部分燃烧时,平均指示压力和指示热效率的变动较小,且随混合气浓度增加而减小。In this paper, the combustion stabilities and cycle-to-cycle variations of n-heptane homogeneous charge compression ignition （HCCI） combustion were investigated. In-cylinder pressures of 100 combustion cycles under typical operation conditions including partial burn, normal combustion and knock combustion were recorded. Consequently, cycle-to-cycle variations of combustion parameters and performance parameters were analyzed. The results reveal that, the cycle-to-cycle variations of the ignition timing, initial temperature, and crank angle corresponding to the peak heat release value are less than 3%. The variations of the second combustion stage are strongly affected by equivalence ratio and substantially improved with the increase of the fuel concentrations. The cycle-to-cycle variations and COVs of peak values of the cool flame and hot flame show obviously increase with the increase of fuel supply rate. Regarding to the performance pa- rameters, variations of maximum pressure and pressure rise rate is very small except for the knock combustion. On the contrary, cycle-to-cycle variations of mean indicated pressure and indicated thermal efficiency are very small except for the partial combustion, and variations decrease with the increase of the fuel supply rate.

关 键 词：内燃机 均质充量压缩着火 正庚烷 燃烧稳定性 循环变动 

分 类 号：TK464[动力工程及工程热物理—动力机械及工程]