摘要
In this work,the spray behaviors of a rotary atomizer with round-shaped injection orifices are experimentally investigated to study the breakup mechanism and spray characteristics using RP-3 as the liquid fuel.The breakup process of the liquid is visualized by the backlight shadow imaging method,which also provides the measurements of liquid breakup length and penetration height.The injection mode of the liquid film is observed using the front-light illumination method.The droplet size and distribution are measured using the laser particle size analyzer at various radial locations.Three typical breakup modes are identified:the ligament breakup mode,bag breakup mode,and shear breakup mode.Aerodynamic Weber number(Wed)and momentum flux ratio(q)are used to elaborate the liquid breakup regimes.Results of droplet sizing indicate that the Sauter mean diameter decreases with a higher rotational speed and slightly varies with the volume flow rate.A correlation between liquid breakup modes and non-dimensional droplet size is established based on Wed and q.This study presents some significance for understanding the impacts of the rotational speed and volume flow rates on the spray performance of actual aviation fuels in rotary atomizers.
为深入研究甩油盘中液体的破碎机理和喷雾特性,本文采用RP-3作为液体燃料,对一种圆形喷孔甩油盘的喷雾行为进行了试验研究.采用阴影成像的方法对液体的破碎过程可视化,同时进行了液体破碎长度和穿透深度的测量.利用前端照明的方法观察液膜的喷射模式.采用激光粒度分析仪对不同径向位置处的液滴尺寸和分布进行测量.确定了三种破碎模式:袋装破碎、韧带破碎和剪切破碎.采用气动韦伯数和液气动量比描述液体的破碎模式.结果表明:索太尔平均直径随着转速的升高而降低,但受燃油流量的影响较小.基于气动韦伯数和液气动量比,建立了液体破碎模式与无量纲液滴尺寸的关系.该研究对于了解甩油盘中转速和燃油流量对实际航空燃料雾化性能的影响具有一定的意义.
基金
supported by the National Science and Technology Major Project of China(Grant No.J2019-III-0006-0049).
