横向气流中的液体圆形射流破碎实验

采用了高速摄像仪对横向气流场中的液体圆形射流破碎过程进行了研究.实验中使用的喷嘴喷孔直径为0.3 mm,研究液体工质采用水,液气两相动量通量比的范围为10.2～80.结果表明,射流表面初始波动是蛇形波动,在气动力作用下逐渐发展成螺旋状表面波,最终增长到一定程度使得液体断开.随着气流速度的增加,气动力在射流破碎过程中将取代表面张力而占据主导地位,而且螺旋状表面波幅值会随气流速度增加而增加.射流运动轨迹脉动幅度随气流速度增加而增强,随射流速度增加而减弱.同时给出了射流破碎位置坐标与液气两相动量通量比之间的关系式,以及射流液柱在破碎点之前类似抛物线的轨迹曲线公式.

Experiment on the breakup of round liquid jets in cross airflows

An experiment was conducted to investigate the breakup processes of round liquid jets in cross airflow with a high-speed video camera.The orifice diameter of the nozzle was 0.3 mm and the liquid used in the test was water.The liquid-to-air momentum flux ratio varied from 10.2 to 80.The results indicate that the initial surface waves are sinuous,which will be developed into spiral waves by aerodynamic force.When the spiral waves grow large enough,the liquid column will be either pinched due to surface tension or cut by aerodynamic force,depending on the cross airflow velocity.The amplitude of the spiral wave is increased with the rising cross airflow velocity.The fluctuations of the liquid jets trajectories are larger for higher airflow velocities,and weaker for higher liquid jet velocities.The correlations between the coordinates of the jet breakup locations and the liquid-to-air momentum flux ratio were concluded.The equation of the trajectory like parabola curve was derived for the jet column trajectory before breakup.