高韦伯数条件下黏性对液滴变形过程的影响  

Viscous effect on the droplet deformation process under high Weber number conditions

作　　者：申帅[1,2] 李建玲 刘金宏[2] 范玮[1] SHEN Shuai;LI Jianling;LIU Jinhong;FAN Wei(School of Power&Energy,Northwestern Polytechnical University,Xi’an,710129,Shaanxi,China;National Key Laboratory of Shock Wave and Detonation Physics,Institute of Fluid Physics,China Academy of Engineering Physics,Mianyang 621999,Sichuan,China)

机构地区：[1]西北工业大学动力与能源学院,陕西西安710129 [2]中国工程物理研究院流体物理研究所,四川绵阳621999

出　　处：《爆炸与冲击》2020年第12期86-97,共12页Explosion and Shock Waves

基　　金：国家自然科学基金(11772309);NSAF联合基金(U1730134);科学挑战专题(TZ2016001);西北工业大学博士生创新基金(CX201949);冲击波物理与爆轰物理重点实验室基金(6142A03180304)。

摘　　要：为探究液滴黏性对变形过程的影响,深入了解液滴在冲击波作用下变形破碎的行为机制。采用高速阴影技术在水平激波管上拍摄了高韦伯数(We=1 100~4 400)条件下,3种黏性硅油液滴的变形过程。结果表明随着黏性的提升:液滴演化出相应特征所需时间增大,同时会出现新的变形特征;液滴空间及位移特征参数的生长速率降低而变形时间、最大变形高度/位移都增大,这是因为提升的黏性力降低了变形速率、耗散了更多的动能并延长了液滴的变形过程;液滴表面最不稳定的Kelvin-Helmholtz波朝着大尺度、低生长率的方向发展,从而实现黏性对变形过程的延缓作用。随着最大变形位移的增大,最大变形高度首先线性增长,之后增幅降低。To explore the effect of droplet viscosity on the deformation process,and have a deep understanding of the mechanism of the droplet deformation and breakup process.Droplet deformation behaviors of three viscous silicone oils were experimentally captured by the high-speed shadowgraphic technique on a horizontal shock tube,the Weber number(We)ranged between 1100~4400.Results show that with the increasing of droplet viscosity:new deformation characteristics appear,and the duration that the droplet evolves into the special shape increases;The growth rates of characteristic space and displacement parameters all decrease,while the duration of the deformation process,the maximum of the droplet deformation extent/displacement all increase.This is because the enlarged viscous force has slowed down the deformation rate,consumed more inertia,and extended the deformation process;The most unstable wave of Kelvin-Helmholtz instability develops toward a larger scale and a slower growth rate tendency,thus the delaying effect caused by the viscosity on the deformation process is achieved.With the increasing of the maximum of deformation displacement,the maximum of droplet deformation extent firstly shows a linear growth trend then a slower growth rate.

关 键 词：激波 液滴黏性 变形过程 高韦伯数 KELVIN-HELMHOLTZ不稳定性 

分 类 号：O351[理学—流体力学]