压力涡流喷油器喷嘴结构因素对喷雾特性的影响

采用MIXTURE双相流数值模拟的方法研究压力涡流喷嘴结构因素对形成中空锥喷雾的影响。喷孔直径由0．5mm增大到1mm时，喷雾贯穿距离减少约60％，空心锥角增大7．5倍；喷孔长度由0．6mm增大到1mm时，喷雾贯穿距离增大约1．4倍，空心锥角减少约40％；有轴针时，空心锥角增加约4倍；改变轴针形状，将轴针头部加工成锥形，空心锥角增加约30％。喷孔内、外有无圆角对喷雾空心锥角大小的影响幅度在30％-40％。研究结果表明：喷孔长径比、喷孔入口处喷孔形状与轴针形状的配合和喷孔出口端形状是影响压力涡流喷嘴空心锥特性的重要因素。

Influence of Structure Factor of Pressurized Swirl Injector on Spray Characteristic

The influence of structure factor of pressurized-swirl injector nozzle on hollow cone spray was studied by using MIXTURE dual phase flow numeric simulation method. When the nozzle diameter increases from 0.5 mm to 1 mm, the spray penetration distance decreases by 60% and the hollow spray cone angle increases by 7.5 times. When nozzle length increases from 0.6 mm to 1 mm, the spray penetration distance increases by 1.4 times and the hollow spray cone angle decreases by 40%. The hollow spray cone angle increases by 4 times by using the injector with axis needle and modification of needle configuration, such as processing the needle head into cone shape, can also increase the hollow spray cone angle by 30%. The variety scope of the hollow spray cone is about 30% - 40% for there is a fillet at the nozzle entrance and the nozzle exit or not. The study shows that the factors such as ratio of injector nozzle length to diameter, coordination of shape of nozzle and needle at the nozzle entrance, nozzle shape at nozzle exit are the important factors that influence the spray characteristic of pressurized-swirl injector.