论文部分内容阅读
为了获得有限空间内喷雾在横流影响下的掺混发展及机理,应用PIV系统测量了单个旋流雾化喷嘴产生的喷雾在横流中的掺混流场,实验在矩形通道内实施。获得了3种喷嘴入射角度和3种液气动量比下的掺混截面流场结构。结果表明,由于射流撞击、剪切和壁面约束作用,流场中形成前缘涡和反旋涡对,反旋涡对对掺混起了主要作用。比较不同喷嘴入射角度和液气动量比下的流场结构发现,随喷雾入射角度减小,两相作用提前发生,且反旋涡对尺度小,更利于掺混均匀;随液气动量比减小,气相作用增强,旋涡强度和尺度变小,更小的涡尺度更利于液滴均匀分布。
In order to obtain the mixed development and mechanism of spray in a confined space under the influence of cross flow, a PIV system was used to measure the mixed flow field of the spray generated by a single swirl atomizing nozzle in a cross flow. Experiments were carried out in a rectangular channel. The flow field structure of the mixed cross section was obtained under three kinds of nozzle angles and three kinds of liquid-vapor momentum ratios. The results show that due to jet impact, shear and wall constraints, the formation of the leading edge vortex and anti-vortex pairs in the flow field, the anti-vortex pairs play a major role in the mixing. Comparing the flow field structures at different angles of incidence and the hydrodynamic ratio, it is found that the two-phase action takes place ahead of time with the decrease of incident angle of the spray and the size of the anti-vortex is small, which is more conducive to blending. With the decrease of the momentum-momentum ratio , Enhance the gas phase, vortex intensity and scale become smaller, smaller vortex scale is more conducive to the uniform distribution of droplets.