横向气流对空心锥形喷雾液滴群的夹带特性

空心锥形喷雾与横向气流的掺混是强化气液掺混的一种重要方式,目前对这一过程尚缺乏深入研究。为了研究横向气流对空心锥形喷雾射流液滴群的夹带特性,采用PIV可视化技术对掺混流场进行测量。结果表明:空心锥形喷雾与横流的相互作用在气流流向方向上诱导出现明显的剪切层及不稳定涡结构,对雾化液滴的扩散产生重要影响并引起液滴在剪切层区域的富集。在分析横流雷诺数、喷雾液滴雷诺数与液滴数流率对掺混流场剪切层结构影响规律的基础上,基于量纲分析和回归分析方法,建立了空心锥形喷雾与横向气流掺混流场中剪切层轨迹线的无量纲预测关联式。

Entrainment Characteristics of Hollow Cone SprayDroplets in Crossflow

The interaction of hollow cone spray and crossflow is an important way to enhance the mixing of gas and liquid, but there is rare research to clarify the mechanism of this motion. Adapting PIV system, the characteristics of shear layer and droplet dispersion of hollow cone spray in crossflow were investigated. The results show that shear layer and unsteady vortex structure are induced in the direction of flow field, enhancing the diffusion of droplets and causing the concentration of droplets in the shear layer region. Three parameters including crossflow Reynolds number, droplet Reynolds number and flow rate of droplet quantity directly affect the shear layer structure in the mixing flow field. With dimensional and regression analysis, a predictive correlation for shear layer trajectories in mixing flow field is developed.