【摘要】 利用详细的化学动力学机理与CFD多维数值模拟计算软件研究了燃烧室结构参数对分隔室压燃式天然气发动机燃烧特性的影响。为验证模型的正确性,将实验值与计算值进行了对比。通过模拟计算,讨论了燃烧室通道截面积、通道倾角、通道形状、通道布置对着火时刻、缸内平均温度和压力以及NO排放的影响。结果表明:通道截面积在132.66 mm2时综合性能最佳;通道倾角为50°时能取得较好的燃烧性能;圆形通道在着火性能、NO排放性能均优于圆角方形通道;通道布置方式对燃烧性能的影响较小。更多还原

【Abstract】 Effects of combustion chamber parameters on combustion characteristics were studied in a compression ignited natural gas engine with separated chamber by coupling the detailed chemical kinetic mechanism with multi-dimensional Computational Fluid Dynamic(CFD) code.Calculated data were compared with experimental data to verify the model predictability.The effects of structural parameters of combustion chamber,such as the passage area,the orientation,the cross-section shape and the position,on ignition timing,cylinder pressure,temperature and NO mass fraction were discussed.Results show that the optimum passage area is 132.66 mm~2,and satisfactory combustion characteristics was obtained with passage orientation of 50° to piston moving direction,the circle-section passage gives better ignition characteristics and lower NO emission compared with those of the rounded-square passage,and passage orientation has small influence on combustion characteristics.更多还原