加气喷嘴气体注入形式对雾化性能的影响

INFLUENCE OF GAS-INJECTOR GEOMETRY ON ATOMIZATION PERFORMANCE OF AERATED-LIQUID NOZZLES

关键词:  燃料雾化  燃料喷射  涡轮喷气发动机

Key words:  Fuel pulverization  Fuel spray  Turbojet engine

摘要:

本文用马尔文粒度分析仪测量喷雾的平均液滴尺寸及液滴尺寸分布,研究了气体注入形式对喷雾特性的影响.喷嘴压降为34.5～690kPa,喷嘴气液比为0.002～0.023.试验中使用了两种气体注入形式:一种是直径6.3mm的单孔,另一种是20个直径0.5mm的小孔.它们与三种不同孔径的喷孔配合使用.其孔径分别为0.8,1.6和2.4mm.研究结果表明,雾化质量主要取决于喷嘴压降和气液比,而对气体注入形式和喷孔直径不敏感.测量液体流量看出,此类喷嘴的流量系数很小.雾化液体中含有固体颗粒或其它易堵塞小孔或喷嘴通道的有害物时,使用这种喷嘴将会显示出它的优点.

Abstract:

The atomizing performance of an aerated-liquid nozzle is examined with special emphasis on the influence of gas-injector geometry on spray characteristics .A Malvern spray analyzer is used to measure mean drop sizes and drop-size distributions.All measurements are carried out when spraying water into air at normal atmospheric pressure and temperature. Two configurations were selected to provide a wide variation in gas-injector geometry.The results show that atomization quality depends mainly on injection pressure and gas/liquid ratio, and is less sensitive, to gas-injector geometry and injector-orifice diameter. This could prove very advantageous in applications where the liquid to be atomized contains solid particles or contaminants that would tend to block the small holes and passages of conventional nozzle.