Effective liquid fuel atomization is an ultimate aim for the prefilming airblast atomizer in aero-engines, and the liquid fuel breakup behavior is the key indicator of atomization quality. Whereas, the prefilmer lip structure is unnoticed but of great influence on this breakup process. In this paper, the rectangular block structured prefilmer lip and the triangular prism structured prefilmer lip are delicately designed and adopted in planar prefilming airblast atomization. Accordingly, the spray characteristics, including the liquid film morphology, droplet distributions, and atomization quality are comprehensively investigated under structured prefilmer lips, using a coupled LB-LES model. The numerical results reveal that when the rectangular block structured prefilmer lip is adopted, the multihole morphology appears on the liquid film under the cutting effect of the rectangular sawtooth, thus contributing to the liquid breakup process. The droplet equivalent diameter in the atomization process distributes exponentially, and 70%-80% of the droplet sizes are less than 100 μm. The droplet velocity shows a normal distribution with its average value located from 1 m/s to 2 m/s in the streamwise direction when the air velocity is 20 m/s. Ultimately, according to droplet size, droplet velocity, and atomization angle, along with the atomization efficiency coefficient, the atomization quality under the rectangular block structured prefilmer lip is better than that with triangular prism structured prefilmer lip and unstructured prefilmer lip, and the highest atomization quality is obtained with rectangular block width of 0.3 mm.

液体燃料的有效雾化是航空发动机预膜鼓风雾化器的最终目标，液体燃料的破碎行为是雾化质量的关键指标。然而，prefilmer 唇缘结构未被注意到，但对该破碎过程有很大影响。本文在平面预膜鼓风雾化中精心设计并采用了矩形块结构预膜唇和三棱柱结构预膜唇。因此，使用耦合的 LB-LES 模型，在结构化预膜唇下全面研究了喷雾特性，包括液膜形态、液滴分布和雾化质量。数值结果表明，当采用矩形块结构预膜器唇口时，在矩形锯齿的切割作用下，液膜上出现多孔形貌，从而有助于液体破碎过程。水滴雾化过程中当量直径呈指数分布，70%-80%的雾滴尺寸小于100 μm。当空气速度为20 m/s时，液滴速度呈正态分布，其平均值在流向方向上位于1 m/s至2 m/s之间。最终，根据液滴尺寸、液滴速度和雾化角度，以及雾化效率系数，矩形块结构预膜唇下的雾化质量优于三棱柱结构预膜唇和非结构预膜唇，雾化最高质量是用 0.3 毫米的矩形块宽度获得的。