喷嘴入射方式对气体-液滴群掺混的影响  

Effect of different injection angles on gas-droplets two-phase flow mixing characteristics

作　　者：孙慧娟[1] 白博峰[1] 张海滨[1] 刘利[1] 

机构地区：[1]西安交通大学动力工程多相流国家重点实验室,西安710049

出　　处：《固体火箭技术》2009年第5期492-495,510,共5页Journal of Solid Rocket Technology

基　　金：国家自然科学基金创新群体(No.50521604)

摘　　要：通过数值模拟的方法从冷态方面研究了金属/水反应冲压发动机二次掺混室内横流气体和通过压力旋流喷嘴雾化的液滴群的掺混情况。提出了掺混度、不均匀浓度因子和等浓度线这3种特征量作为评价指标,分析了不同喷嘴入射角度情况下,液滴群对横向交叉气流的影响以及气流对液滴群掺混的作用。结果表明,液滴群的加入使气流中产生了尺度不同的涡,促进了湍流;喷嘴附近的掺混初始阶段,大涡作用使液滴分布很不均匀,喷嘴下游,涡的尺度减小,对液滴的扩散影响减弱,但初始的喷雾形态和液滴趋向高应变和低涡量区域造成了壁面处液滴浓度仍然高于其他区域;喷嘴垂直无偏入射的掺混优于轴向或切向入射;轴向向上游偏转入射优于向下游偏转入射;切向偏转角度越大,越不利于掺混。Based on the combustion of the water ramjet, the mixing characteristics of droplets through a turbulent crossflow in the cold flow field were investigated by using the numerical simulation method. The droplets were generated by four hollow cone pressure-swirl nozzles. The degree of mixing, uneven concentration factor and isoconcentration line were proposed to assess the mix- ing effect. The inter-impact of the crossflow and droplets at different injection angles of nozzles were analyzed. The results reveal that different-scale eddies are generated from adding of droplets into the crossflow, leading to the increase of turbulence intensity. The droplets distribute unevenly due to the big eddies near the nozzles. And the energy attenuation of the eddies account for the weak droplet dispersion after the nozzles. However, the droplets tend to congregate in the near-wall regions on account of both the initial spray configuration and the tendency of droplets＇congregating in high strain and low vortex regions. The mixing effect with the injection of nozzles to the upper flow is better than that to the down flow, but the unbiased injection is the best of all the injection angles. The mixing result becomes worse with the increase of tangential angle .

关 键 词：气体-液滴两相流 入射角度 数值模拟 掺混 

分 类 号：V430[航空宇航科学与技术—航空宇航推进理论与工程]