旋流喷嘴中空旋转射流近区域流动的研究

从理论上分析了旋流喷嘴喷出的中空射流近区域的液膜的运动，在只考虑液膜表面张力的作用下，应用质量守恒和动量定理，建立了描述液膜运动的非线性常微分（积分）方程组，该方程组可以用数值方法方便地求解，结果表明，液体离开旋流喷嘴后在自由空间形成的液膜呈葫芦形状，其速度和液膜厚度等都周期性地变化。本结果是在液厝受拓动失称碎成液滴前的最基本运动状态，可以在射流的近区域内实验观察到，也是进一步从理论液膜破碎雾化过

Study on the Flow in the Near Field of Swirling Hollow Jet from Swirl Nozzle

The liquidsheet flow in the near region from swirl nozzle was analyzed theoretically. Surfacetension force was considered as the ruling factor, and a set of non-linear differential(integral) equations describing the liquid sheet flow was conducted using the theorem ofmomentum. The equations were solved by digital calculation. The results showed that thesheet in space was a multi-tulip shaped hollow jet, whose velocity and sheet thicknesschanged periodically along the nozzle axis. The results can be considered as the basic jetflow pattern from swirl nozzle before the liquid sheet is broken up into droplets by itsinstability and perturbation in practical jets as observed in experiments.