The advances in technology demand more accurate methods of spray formation for combustion purposes. One of the most common techniques to produce fine droplets is the jet in crossflow method. There are many parameters such as nozzle geometry, working fluid properties, and ambient conditions that affect spray characteristics. The main concern in the present research is to investigate the impact of nozzle shape and its dimensions on the size distribution of droplets in the primary zone. Accordingly, circular and rectangular geometries with different sizes are considered to examine shape effect. The shadowgraph method, with a pulsed LED illumination technique, is employed to capture high-resolution images. The gas Weber number and momentum ratio varied within 9−19 and 50−110, respectively. The results indicated that the droplet morphology is almost independent of nozzle geometry. On the other hand, the circular nozzle produced droplets with a smaller size in Sauter mean diameter (SMD) compared to the rectangular one. The rectangular coflow orifice had the worst function among the others. Furthermore, the orifice size had a noticeable influence on the droplet size. Nozzles with smaller dimensions provided droplets with a smaller size in SMD. Regardless of the nozzle shape, the SMD was reduced with both gas and liquid Weber numbers.

中文翻译：

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初级破碎区内交叉流动的射流的液滴特性：喷嘴形状和尺寸的影响

技术的进步需要更精确的用于燃烧目的的喷雾形成方法。产生细液滴的最常用技术之一是交叉流喷射法。影响喷雾特性的参数有很多，例如喷嘴几何形状、工作流体特性和环境条件。本研究的主要关注点是研究喷嘴形状及其尺寸对初级区域液滴尺寸分布的影响。因此，考虑具有不同尺寸的圆形和矩形几何形状来检查形状效果。采用脉冲 LED 照明技术的阴影图方法用于捕获高分辨率图像。气体韦伯数和动量比分别在 9-19 和 50-110 范围内变化。结果表明，液滴形态几乎与喷嘴几何形状无关。另一方面，与矩形喷嘴相比，圆形喷嘴产生的 Sauter 平均直径 (SMD) 尺寸更小。矩形顺流孔在其他孔中功能最差。此外，孔口尺寸对液滴尺寸有显着影响。较小尺寸的喷嘴在 SMD 中提供较小尺寸的液滴。无论喷嘴形状如何，气体和液体韦伯数都降低了 SMD。孔口尺寸对液滴尺寸有显着影响。较小尺寸的喷嘴在 SMD 中提供较小尺寸的液滴。无论喷嘴形状如何，气体和液体韦伯数都降低了 SMD。孔口尺寸对液滴尺寸有显着影响。较小尺寸的喷嘴在 SMD 中提供较小尺寸的液滴。无论喷嘴形状如何，气体和液体韦伯数都降低了 SMD。