正庚烷/生物柴油双燃料的部分均质压燃燃烧  

Partial Homogeneous Charge Compression Ignition Combustion of n-Heptane/Biodiesel Dual Fuel Engine

作　　者：吕兴才[1] 马骏骏[1] 吉丽斌[1] 黄震[1] 

机构地区：[1]上海交通大学动力机械与工程教育部重点实验室,上海200240

出　　处：《燃烧科学与技术》2009年第3期203-208,共6页Journal of Combustion Science and Technology

基　　金：高等学校博士学科点专项科研基金资助项目(20070248112)

摘　　要：研究了气口喷射正庚烷、缸内直喷生物柴油的部分均质充量压缩着火（HCCI）燃烧的燃烧特性和排放特性．研究表明，整个燃烧过程呈现三阶段放热模式．随着正庚烷预混合比例的增加，第一阶段和第二阶段最大放热率呈线性增加，从而导致生物柴油着火时的温度和压力明显上升．预混合正庚烷的引入使得放热中心时刻和放热结束时刻明显提前，燃烧持续时间缩短．至于排放方面，预混合比例的增加会引起CO和HC排放的增加，并且增加幅度逐渐减小；在中小当量比下，预混合比例增加会使得NOx排放线性降低，但是对碳烟排放却几乎没有影响；在较大当量比下，预混合比例增加可以使得NOx和碳烟排放同时大幅度下降，并且在20％～25％之间可以得到最佳的NOx和碳烟降低效果．The combustion characteristics and emissions of partial homogeneous charge compression ignition （HCCI） combustion of biodiesel/n-heptane dual fuel engine were investigated. The experimental results reveal that the heat release curves exhibit three-stage combustion. With the increase of premixed ratio of n-heptane, the peak values at the first- and second-stage both increase linearly. It is worth noting that large premixed ratio of n-heptane will lead to unacceptable pressure rising rate at large equivalence ratio. As to the regulated emissions, partial substitute for biodiesel by n-heptane increased CO and HC emissions. At small and medium equivalence ratios, premixed combustion of heptane leads to the decreasing of NO, emission, but has little effect on smoke opacity. At large equivalence ratio, it is very interesting to find that both NOx and smoke opacity are suppressed substantially, and the optimal effect will be achieved with the n-heptane premixed ratio of 20%--25%.

关 键 词：生物柴油 正庚烷 部分均质充量压缩着火 燃烧特性 排放 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]