翻转实验中瑞利泰勒不稳定性引致的血液湍流前锋运动及有限时间爆破  

Turbulent front advancement of blood in rayleigh-taylor instability by overturning experiment and finite time blow-up

作　　者：李熙[1,2] 

机构地区：[1]河海大学海岸灾害及防护教育部重点实验室,南京210098 [2]河海大学交通与海洋工程学院,南京210098

出　　处：《水动力学研究与进展（A辑）》2008年第2期226-229,共4页Chinese Journal of Hydrodynamics

摘　　要：在实验室中翻转两层或三层的非牛顿液体,初始分层是稳定的。翻转水箱具有相对较小的厚度,翻转后产生的湍流是虚三维的(Pesdo-3D),瑞利泰勒不稳定性起动了湍流混合过程及前锋的行进。时间的典型测量是从最初稳定的时间开始后两妙,而翻转过程的是大约1秒,本文采用相对密度的均方根扰动分析了两组数据,关于反转涡系级联(cascade)的有限时间爆破的猜想首次在实验通过定义两个特征时间被证实:均方根扰动(RMS)的第一个峰值时间,T1;湍流前锋触底时间,Tf,得出结论,当引入标量时间ts1时,T1/ts1逼近Tf。Abstract： A laboratory study of mixing in non-Newton fluids of blood was conducted by overturning a tank of initially stable stratified fluids of two or three layers. The tank was of comparably small thickness and the turbulence subsequent to the instabilities was pseudo-3D. The Rayleigh-Taylor instabilities initiated the turbulent mixing and front advancement of turbulence. Typically the measurement was started 2 seconds calculated from initial stable condition and the overturning process is about 1 second, two sets of data were analyzed by excess density RMS （root mean square） fluctuation, conjecture of finite time blow-up of overturned eddies cascade was confirmed first in laboratory by relating two characteristic times： the first peak time of RMS, T1; front reaching lower boundary time, Tf. It is concludedT1 / ts1 approximates Tf by introducing a scalar of time scale ta1.

关 键 词：不稳定性 湍流 色谱浓度法 有限时间爆破 级联 

分 类 号：TV131[水利工程—水力学及河流动力学]