Detail characterization of the liquid jet core in a model cross-stream airblast atomizer by application of the Optical Connectivity (OC) technique is the goal of the present paper. The unique ability of the technique in imaging the fluorescence signal exclusively from the jet core region facilitates simultaneous visualization of the liquid jet from the side- and the front-view with high background contrast. This allows measurement of some important primary breakup characteristics. The jet penetration and breakup length are obtained from the side-view images, while the front view images provides the jet width and the spreading angle. The above parameters are measured for a wide range of injector operating conditions. The measurement of mean jet trajectory and mean penetration/breakup length indicated large difference in comparison to the past studies based on experiments conducted in wind-tunnels. This is attributed to air flow confinement within the atomizer in the present case and also accurate measurement of breakup location in the OC technique. The range of the measured mean width of the jet and spreading angle indicated ’sheet breakup mode’ of the liquid jet for all injector operating conditions. Correlations are obtained to describe the evolution of different mean quantities with respect to relevant non-dimensional numbers. The fluctuations of jet breakup parameters are also measured. Some interesting correlations are obtained between fluctuations of different primary breakup characteristics which are discussed in the paper.

本论文的目标是通过应用光学连接 (OC) 技术对模型横流喷气雾化器中的液体喷射核心进行详细表征。该技术在对射流核心区域的荧光信号进行成像方面的独特能力有助于同时从侧面和正面观察具有高背景对比度的液体射流。这允许测量一些重要的初级破碎特性。射流穿透和破碎长度从侧视图像中获得，而前视图像提供射流宽度和扩散角。上述参数是针对各种喷射器操作条件测量的。与过去基于风洞实验的研究相比，平均射流轨迹和平均穿透/分裂长度的测量表明存在很大差异。这归因于本案例中雾化器内的气流限制以及 OC 技术中对破裂位置的准确测量。射流的测量平均宽度和扩散角的范围表明在所有喷射器操作条件下液体射流的“薄片破碎模式”。获得相关性以描述不同平均量相对于相关无量纲数的演变。还测量了射流破碎参数的波动。在论文中讨论的不同初级破裂特征的波动之间获得了一些有趣的相关性。