The atomization process and fuel placement inside a gas turbine fuel injector are investigated at realistic operating conditions to understand the role of individual flow processes and hardware components. A high pressure, high temperature spray test facility is developed that can simulate a wide range of aero-engine operating conditions. The fuel injector is a swirl cup - dual orifice nozzle combination which is used in the rich dome combustors of various aero-engines. The internal flow field is captured using time-resolved laser induced fluorescence imaging and phase Doppler interferometry measurements. A stage-wise characterization is adopted to track the spray formation as the flow evolves through the swirl cup. The fuel placement at the cup exit is mainly decided by pilot nozzle spray characteristics and the relative momentum exchange between the gas and liquid phases. At the swirl cup exit, two class of droplets are formed: (1) droplets originated directly from the pilot nozzle, which are convected downstream by the primary air swirl, (2) droplets originated from the rim, which are atomized by the shear layer. The relative percentage of these two droplet classes depends on the pilot nozzle operation at low and high power conditions. The effect of primary spray and wall-filming are minimal towards improving the atomization. In both low and high power operating cases, the counter-rotating shear layer interactions are identified as the major mechanism that is improving the atomization process in swirl cup.

在实际运行条件下研究了燃气轮机喷油器内的雾化过程和燃料放置情况，以了解各个流动过程和硬件组件的作用。开发了一种高压，高温喷雾测试设备，可以模拟各种航空发动机的运行条件。喷油器是涡流杯-双孔喷嘴组合，用于各种航空发动机的浓圆顶燃烧室。使用时间分辨激光诱导的荧光成像和相位多普勒干涉测量法来捕获内部流场。当流动通过涡流杯时，采用阶段性特征来跟踪喷雾的形成。杯出口处的燃料放置主要取决于先导喷嘴的喷雾特性以及气相和液相之间的相对动量交换。在旋杯出口处，形成两类液滴：（1）直接从引燃喷嘴产生的液滴，这些液滴通过一次空气旋流在下游对流；（2）从轮缘产生的液滴，这些液滴被剪切层雾化。这两种液滴类别的相对百分比取决于在低功率和高功率条件下的引燃喷嘴操作。初次喷涂和壁涂的效果对于改善雾化作用很小。在低功率和高功率两种情况下，反向旋转的剪切层相互作用都被认为是改善旋流杯雾化过程的主要机理。形成两类液滴：（1）直接来自引燃喷嘴的液滴，这些液滴通过一次空气旋流在下游对流；（2）来自轮辋的液滴，它们被剪切层雾化。这两种液滴类别的相对百分比取决于在低功率和高功率条件下的引燃喷嘴操作。初次喷涂和壁涂的效果对于改善雾化作用很小。在低功率和高功率两种情况下，反向旋转的剪切层相互作用都被认为是改善旋流杯雾化过程的主要机理。形成两类液滴：（1）直接来自引燃喷嘴的液滴，这些液滴通过一次空气旋流在下游对流；（2）来自轮辋的液滴，它们被剪切层雾化。这两种液滴类别的相对百分比取决于在低功率和高功率条件下的引燃喷嘴操作。初次喷涂和壁涂的效果对于改善雾化作用很小。在低功率和高功率两种情况下，反向旋转的剪切层相互作用都被认为是改善旋流杯雾化过程的主要机理。这两种液滴类别的相对百分比取决于在低功率和高功率条件下的引燃喷嘴操作。初次喷涂和壁涂的效果对于改善雾化作用很小。在低功率和高功率两种情况下，反向旋转的剪切层相互作用都被认为是改善旋流杯雾化过程的主要机理。这两种液滴类别的相对百分比取决于在低功率和高功率条件下的引燃喷嘴操作。初次喷涂和壁膜的作用对于改善雾化作用很小。在低功率和高功率两种情况下，反向旋转的剪切层相互作用都被认为是改善旋流杯雾化过程的主要机理。