单喷嘴横流气雾两相流掺混实验研究

采用PIV设备测量了方腔通道内气体液雾两相交叉横向流的掺混,液滴通过旋流雾化喷嘴产生,获得了沿横流方向不同掺混横截面的液滴分布图和液滴运动流线图.比较了三种喷嘴布置角度(60°,90°,120°)在不同气流速度下的掺混效果.结果表明:在横流作用和壁面约束的影响下,流场中出现不同尺度的漩涡,大涡的卷吸与离心作用导致液滴分布不均匀,影响了雾滴与气相的掺混.随着掺混的发展,大涡的强度和尺寸均减小,对雾滴影响减弱,掺混变好;三种喷嘴布置角度下,60°掺混最好,90°次之,120°最差.

EXPERIMENTAL STUDY Of TURBULENT MIXING OF SPRAY DROPLETS IN CROSSFLOW WITH A SINGLE NOZZLE

An experimental investigation of two-phase turbulent mixing of spray droplets with crossflow in a rectangular duct is presented.The liquid droplets are produced by a pressure swirl nozzle.The distribution of water droplets on the cross section and the flow vector field are measured with PIV technology.The effects of a nozzle injection angle(60°,90°or 120°)and cross airflow velocities in the mixing process are addressed.We conclude that the entrainment and centrifugal force of large vortex leads to uneven droplet distribution and exerts influences on the mixing of droplets and cross flow.Both the strength and the size of large eddies decrease with the mixing development,resulting in weak impact on the droplet.Among three injection angles of nozzle,the nozzle with 60°has the best mixing effect,the nozzle with 90°take second place,and the nozzle with 120°is the worst.