Deposition of shear-thinning viscoelastic fluids by an elongated bubble in a circular channel regarding the weakly elastic regime  

作　　者：SungGyu Chun Zhengyu Yang Jie Feng 

机构地区：[1]Department of Mechanical Science and Engineering,University of Illinois Urbana-Champaign,Urbana,Illinois,USA [2]Materials Research Laboratory,University of Illinois Urbana-Champaign,Urbana,Illinois,USA

出　　处：《Droplet》2024年第3期49-56,共8页液滴（英文）

基　　金：American Chemical Society Petroleum Research Fund,Grant/Award Number:61574-DNI9。

摘　　要：Thin-film deposition of fluids is ubiquitous in a wide range of engineering and biological applications,such as surface coating,polymer processing,and biomedical device fabri-cation.While the thin viscous film deposition in Newtonian fluids has been extensively investigated,the deposition dynamics in frequently encountered non-Newtonian com-plex fluids remain elusive,with respect to predictive scaling laws for the film thickness.Here,we investigate the deposition of thin films of shear-thinning viscoelastic fluids by the motion of a long bubble translating in a circular capillary tube.Considering the weakly elastic regime with a shear-thinning viscosity,we provide a quantitative measurement of the film thickness with systematic experiments.We further harness the recently developed hydrodynamic lubrication theory to quantitatively rationalize our experimental observations considering the effective capillary number Cae and the effective Weissenberg number Wie,which describe the shear-thinning and the vis-coelastic effects on the film formation,respectively.The obtained scaling law agrees reasonably well with the experimentally measured film thickness for all test fluids.Our work may potentially advance the fundamental understanding of the thin-film deposi-tion in a confined geometry and provide valuable engineering guidance for processes that incorporate thin-film flows and non-Newtonian fluids.

关 键 词：film WEAKLY BUBBLE 

分 类 号：O35[理学—流体力学]