Dynamics of Developing Laminar Non-Newtonian Falling Liquid Films With Free Surface

1978 ◽  
Vol 45 (1) ◽  
pp. 19-24 ◽  
Author(s):  
V. Narayanamurthy ◽  
P. K. Sarma
Keyword(s):  
Liquid Film ◽  
Power Law ◽  
Mathematical Formulation ◽  
Liquid Films ◽  
Interfacial Shear ◽  
Newtonian Liquid ◽  
Power Law Model ◽  
Falling Liquid Film ◽  
Falling Liquid Films ◽  
Special Case

The dynamics of accelerating, laminar non-Newtonian falling liquid film is analytically solved taking into account the interfacial shear offered by the quiescent gas adjacent to the liquid film under adiabatic conditions of both the phases. The results indicate that the thickness of the liquid film for the assumed power law model of the shear deformation versus the shear stress is influenced by the index n, the modified form of (Fr/Re). The mathematical formulation of the present analysis enables to treat the problem as a general type from which the special case for Newtonian liquid films can be derived by equating the index in the power law to unity.

scholarly journals Effect of Wind Stress on the Dynamics and Stability of Nonisothermal Power-Law Film down an Inclined Plane

2012 ◽  
Vol 2012 ◽  
pp. 1-31 ◽  
Author(s):  
B. Uma
Keyword(s):  
Liquid Film ◽  
Power Law ◽  
Multiple Scales ◽  
Critical Value ◽  
Interfacial Shear ◽  
Newtonian Liquid ◽  
Nonlinear Stability Analysis ◽  
Inclined Plane ◽  
Condensate Film ◽  
Power Law Index

Dynamics and stability of a nonisothermal power-law liquid film down an inclined plane is considered in the presence of interfacial shear. Linear stability characteristics of the power-law liquid film using normal mode approach reveal that isothermal and evaporating films are unstable for any value of power-law index while there exists a critical value of power-law index for the case of condensate film above which condensate film ow system is always stable. This critical value of power-law index increases with the increase in shear stress at the interface. Weakly nonlinear stability analysis using method of multiple scales divulges the existence of zones due to supercritical stability and subcritical instability. The nonlinear evolution equation is solved numerically in a periodic domain. The results reveal that (1) for an isothermal dilatant (pseudoplastic) liquids, the maximum wave amplitude is always smaller (larger) than that for a Newtonian liquid and the amplitude of permanent wave increases with the increase in interfacial shear; (2) condensation of pseudoplastic film happens for the earlier instant of time when the phase change parameter increases and the effect of interfacial shear makes the film more corrugated; (3) dilatant (pseudoplastic) evaporating liquid film attains rupture faster (slower) than that of Newtonian liquid film, and the interfacial shear does not influence the time at which rupture occurs.

Effects Of Surface Solidification on the Stability Of Multi-Layered Liquid Films

1983 ◽  
Vol 105 (1) ◽  
pp. 119-120 ◽  
Author(s):  
S. P. Lin
Keyword(s):  
Stability Problem ◽  
Film Flow ◽  
Liquid Films ◽  
Interfacial Shear ◽  
Capillary Waves ◽  
Inclined Plane ◽  
Air Interface ◽  
The Stability ◽  
Linear Stability Problem ◽  
Special Case

The linear stability problem of a n-layered liquid film with a solidified liquid-air interface is reviewed. The general formulation is applied to the special case of a two-layered film flow down an inclined plane. A stability condition is given explicitly in terms of the density, viscosity and thickness ratios. Based on this condition it is found that solidification of the free surface may have the effects of stabilizing the interfacial shear waves and destabilizing the gravity-capillary waves associated with top-heavy density stratification.

Rivulets formation on a falling liquid film

2015 ◽  
Author(s):  
Sergey Alekseenko ◽  
Aleksey V. Bobylev ◽  
Vladimir V. Guzanov ◽  
Sergey M. Kharlamov ◽  
Alexandr Z. Kvon ◽  
...  
Keyword(s):  
Liquid Film ◽  
Falling Liquid Film

HEAT TRANFER PHENOMENA IN FALLING LIQUID FILMS: A SYNERGISTIC EXPERIMENTAL AND COMPUTATIONAL STUDY

2018 ◽  
Author(s):  
Alexandros Charogiannis ◽  
Fabian Denner ◽  
Berend G. M. van Wachem ◽  
Serafim Kalliadasis ◽  
Christos N. Markides
Keyword(s):  
Computational Study ◽  
Liquid Films ◽  
Falling Liquid Films
Sign in / Sign up

Export Citation Format

Share Document