关于直喷喷雾液相温度分布的研究

Study of Liquid Temperature Distribution of Direct Injection Spray

液体燃料喷雾的蒸发特性对直喷发动机缸内的混合气形成、燃烧过程和有害排放物的形成具有十分重要的影响。在影响液体燃料喷雾蒸发的众多因素中,喷雾气相浓度和液相温度是十分关键的因素。本研究结合双相激光诱导荧光技术和双色法测温技术,对液体燃料直喷喷雾的液相温度分布进行测量研究。研究发现,在一定环境压力条件下,燃料温度对多孔直喷喷雾结构有着显著的影响,且喷雾液相温度分布随喷雾结构的变化而变化。

Evaporation characteristics of fuel spray plays an important role in the gasoline direct injection （GDI） engines, since it significantly influences the mixing of fuel and air, combustion process as well as emission formations.Among the numerous factors which influence the fuel spray evaporation, the vapor phase concentration and liquid phase temperature of the fuel spray are likely the most important ones.Therefore, an optical diagnostic technique combining the laser induced exciplex fluorescence technique and the two-color method has been successfully implemented to study the temperature distribution of liquid phase of fuel spray under various operating conditions.The results reveal that under a certain ambient pressure condition, the liquid fuel temperature has a significant influence on the spray structure, and the temperature distribution of liquid phase of the fuel spray changes according to the variation of the spray structure.