基于燃料特性的汽油机颗粒物排放预测关系式

汽油机的颗粒物排放与所用燃料的性能密切相关.为评价燃料特性对汽油机颗粒物排放的影响,建立了一个简化PN指数(SPNI)关系式并进行了统计学检验.该指数包含T70(70%蒸馏温度)、重芳烃(碳数≥9)含量、终馏点温度和烯烃含量4个关键的燃料参数.在试验和分析过程中配制了代表不同地区市场油的20种模型燃料,并对其燃料参数进行了相关性分析和多元线性回归.发动机试验结果表明,各种典型运行模式下的发动机实际颗粒物数量(PN)排放均与SPNI呈现高度的相关性.与已有的详细PM指数相比,该模型计算更为简便,可操作性强.该简化PN指数可用于工程上评价不同汽油燃料的颗粒物排放潜势.

Predicting formula of particulate matter emission from gasoline engines based on fuel properties

Particulate matter emissions (PM) from gasoline engines are closely related to the fuel used. In order to evaluate the impact of fuel properties on PM emission tendencies from gasoline engines, a simplified PN index (SPNI) formula was developed. The index covers four key fuel parameters of fuel, namely T70 (70% distillation temperature), heavy aromatics content, final boiling point temperature and olefins content. Twenty typical fuels representing market gasoline from different regions were formulated during the process of testing and analysis. Meanwhile, the correlation analysis and multivariate linear regression were performed on the parameters of these fuels. The results of the engine tests show that the actual PN emissions from the engine are highly correlated with the test fuel''s SPNI in various typical operating modes. Compared with the existing detailed PM index (PMI), the SPNI is simpler to calculate and more operable. The SPNI can be used to evaluate the particulate matter emission potentials of different gasoline fuels in engineering.