喷嘴结构参数对喷雾和燃烧特性的影响

Effects of Nozzle Geometry on Spray and Combustion Characteristics

为探究高喷射压力条件下小孔径喷嘴内部结构对燃油喷雾和燃烧特性的影响,采用相位多普勒粒子分析系统(PDPA)和高温定容燃烧弹系统试验研究了采用挤研技术处理的喷嘴与簇孔喷嘴的喷雾与燃烧特性。试验结果表明:相同喷射条件下挤研无助于改善燃油喷雾的索特平均直径(SMD),随着喷孔挤研量的增大,喷雾SMD持续增大,燃烧生成的碳烟量不断增多;随着簇孔间距增大,喷雾SMD先增大后减小,而碳烟生成量表现出相同的变化趋势,簇孔间距为0. 4 mm时,燃烧峰值放热率最高,单孔与0. 2 mm间距簇孔的峰值放热率差别不大。

In order to investigate the effects of internal structure of the small diameter nozzle on fuel spray and combustion characteristics under the condition of high injection pressure, the experiments were carried out to systematically research the spray and combustion characteristics of spray grind nozzle and group - hole nozzle by applying phase doppler particle analysis system （PDPA） and high temperature constant volume bomb system. The results of experiments showed that grind had no contribution to decrease the SMD of fuel spray under the condition of the same injection ; with the increasing grind level of spray nozzle, the SMD together with the amount of soot generated from combustion increased continuously; as the space of group-hole increased, SMD increased firstly and then decreased; the amount of soot formation also showed the same trend; heat release rate roached a peak when the space of group-hole is 0.4 mm, the peak value of the heat release rate between a single hole and the group-hole of 0.2 mm space differs a little.