起动负浮力射流中涡环形成与演化的实验研究  

On the Vortex Ring Formation and Evolution in Negatively Buoyant Jet

作　　者：陈盛文 高磊 

机构地区：[1]四川大学空天科学与工程学院,四川成都

出　　处：《应用物理》2019年第4期182-196,共15页Applied Physics

摘　　要：本文对负浮力涡环的形成与演化的动力学特性进行了实验研究。对小冲程比(L/D = 2、3)情况下产生的浮力涡环的近场的演化进行了分析,发现随着理查德森数Ri增大,涡环的生长半径变大,涡环的运动速度减小,相应的动力学参数(水力冲量、环量等)也变小。并求得浮力涡环的冲量与速度,与细核涡环理论模型公式求得的冲量与速度对比,发现浮力涡环是符合细核涡环特性。In this paper,the formation andevolution of negative buoyancy vortex rings are studied experimentally.Forsmall stroke ratio(L/D=2,3)cases,the evolution of thebuoyant vortex ring in the near field is investigated.It is found that asRichardson number Ri increases,thegrowth rates of the vortex ring radius,as well as its translational velocityare reduced.The kinetic parameters of the buoyant vortex ring,i.e.,the hydrodynamic impulse andcirculation,are also diminished by Ri.The impulse and velocity of the buoyancy vortex ring are obtained and comparedwith those of the thin core vortex ring model.It is found that the buoyantvortex ring conforms to the characteristics of thin core vortex ring model.

关 键 词：负浮力射流 涡环 理查德森数 

分 类 号：O35[理学—流体力学]