基于分形理论的双燃料发动机NO_x排放模拟计算  

Simulation on NO_x Emission of Dual-fuel Engine Based on Fractal Theory

作　　者：汤东[1] 银铭强[2] 来超峰[1] 罗福强[1] 

机构地区：[1]江苏大学汽车与交通工程学院,副教授212013 [2]镇江市江苏大学汽车与交通工程学院

出　　处：《农业机械学报》2008年第9期1-5,14,共6页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家"863"高技术研究发展计划资助项目(项目编号:2006AA11A1B4);内燃机燃烧学国家重点实验室开放基金资助项目(项目编号:2007-05);江苏大学高级人才科研基金资助项目(项目编号:07JDG086)

摘　　要：在双区喷雾卷吸模型的基础上,建立了一个基于皱折火焰面分形理论的双燃料发动机准维模型,来描述双燃料发动机气缸内的湍流燃烧、火焰传播速度等燃烧现象以及排放性能,其中包括滞燃期子模型、喷雾卷吸子模型、燃烧和火焰传播子模型。利用该模型,对一台生物制气-柴油双燃料发动机燃烧过程进行了模拟计算,预测双燃料发动机的NOx排放特性。预测计算结果与实测值的相对误差小于5%。供油提前角提前,生物制气-柴油双燃料发动机NOx排放量增加;相同工况下引燃柴油量减小时,NOx排放量减小。A quasi-dimensional combustion model for a dual-fuel engine was developed based on a double-zone fuel spray entrainment model, which uses fraetal theory to describe the geometry of flamelets in turbulent combustion and its propagation as well as its emission performance. The double-zone fuel spray entrainment model is consisted of ignition delay model, fuel spray and air entrainment model, and flame propagation model. Subsequently, the simulation for combustion processes in a biogas diesel dual-fuel engine was conducted on to forecast its NOx emission characteristics. The relative error between the simulated results and experimental data is no more than 5 %. The NOx emission of the biogas diesel dual-fuel engine increases with the increase of pilot fuel quantity and the advancement of fuel delivery advance angle.

关 键 词：双燃料发动机 燃烧 排放 模拟 分形 

分 类 号：TK421.5[动力工程及工程热物理—动力机械及工程]