Dynamics of Low-Viscosity Liquids Interface in an Unevenly Rotating Vertical Layer  

作　　者：Victor Kozlov Vladimir Saidakov Nikolai Kozlov 

机构地区：[1]Laboratory of Vibrational Hydromechanics,Perm State Humanitarian Pedagogical University,Perm,614990,Russia [2]Institut de Mécanique des Fluides de Toulouse,Toulouse INP,Toulouse,31400,France

出　　处：《Fluid Dynamics & Materials Processing》2024年第4期693-703,共11页流体力学与材料加工（英文）

基　　金：financially supported by the Russian Science Foundation(Project 23-11-00242).

摘　　要：The behavior of two immiscible low-viscosity liquids differing in density and viscosity in a vertical flat layer undergoing modulated rotation is experimentally studied.The layer has a circular axisymmetric boundary.In the absence of modulation of the rotation speed,the interphase boundary has the shape of a short axisymmetric cylinder.A new effect has been discovered,under the influence of rotation speed modulation,the interface takes on a new dynamic equilibrium state.A more viscous liquid covers the end boundaries of the layer in the form of thin films,which have the shape of round spots of almost constant radius;with increasing amplitude of the velocity modulation,the wetting boundary expands.It is found that upon reaching the critical amplitude of oscillations,the film of a viscous liquid loses stability,and the outer edge of the wetting spot collapses and takes on a feathery structure.It is shown that this threshold is caused by the development of the Kelvin-Helmholtz oscillatory instability of the film.The spreading radius of a spot of light viscous liquid and its stability are studied depending on the rotation rate,amplitude,and frequency of rotation speed modulation.The discovered averaged effects are determined by different oscillatory interaction of fluids with the end-walls of the cell,due to different viscosities.The effect of films forming can find application in technological processes to intensify mass transfer at interphase boundaries.

关 键 词：ROTATION OSCILLATIONS immiscible fluids contact line INTERFACE film dynamic equilibrium Nomenclature frot 

分 类 号：O35[理学—流体力学]