双油路离心喷嘴油雾特性试验研究

Experimental Study on Fuel Spray Characteristics of Pressure-Swirl Atomizer

采用高速摄影仪测量某型发动机燃烧室两种大小流量不同的双油路离心喷嘴在不同供油压力下的油雾特性。对煤油从离心喷嘴喷出后，在静止大气中所形成的油雾锥中心截面进行拍摄，并对所得的照片进行图像处理，从而获得油雾锥中心截面上油粒的索太尔平均直径（Sautermeandiameter，SMD）分布、平均SMD以及分布指数N。试验结果表明：（1）小流量喷嘴在副油路单独工作时平均SMD在70．23～86．15μm之间，主副油路同时工作时平均SMD在94．66～109．00μm之间，主油路打开前后，平均SMD变化相差较大，分布指数N在2．76～3．00之间；（2）大流量喷嘴在副油路单独工作时平均SMD在72．77～79．71μm之间，主副油路同时工作时平均SMD在83．53～89．73gm之间，在主油路打开前后，平均SMD变化相差不大，分布指数N在2．79～2．82之间；（3）小流量喷嘴雾化特性与大流量喷嘴雾化特性相比，大流量喷嘴雾化效果稍好。

Fuel spray characteristics of dualorifice pressureswirl atomizers is investigated by using high speed digital video recording devices. The effects of different fuel pressures and two kinds of atomizers, including large flow atomizer and small flow atomizer, are studied respectively. When fuel injects into static atmosphere from dualorifice pressureswirl injectors, raw images are gotten by applied high speed digital video recording devices. And then image analysis software is applied to analyzing these raw ima ges. Finally droplet distribution, mean sauter mean diameter（SMD） and distribution exponent N are obtained. Experimental results show that when research objective is small flow atomizer, the mean SMD varies from 70.23 to 86.15/μm when only secondary fuel passage works, while the mean SMD va ries from 94.66 to 109.00 gm when primary and secondary fuel passages work at the same time. There fore the mean SMD varies greatly whether primary fuel passage works, and the distribution exponent N varies from 2.76 to 3.00. When research objective is large flow atomizer, the mean SMD varies form 72.77 to 79.71 vm when only secondary fuel passage works, while the mean SMD varies form 83.53 to 89.7a μm when primary and secondary fuel passages work at the same time. And the distribution expo nent N varies from 2.79 to 2.82. So the fuel spray characteristics of large flow atomizer is better than that of small flow atomizer.