A Separation Criterion with Experimental Validation for Shear-Driven Films in Separated Flows
The behavior of a shear-driven thin liquid film at a sharp expanding corner is of interest in many engineering applications. However, details of the interaction between inertial, surface tension, and gravitational forces at the corner that result in partial or complete separation of the film from the surface are not clear. A criterion is proposed to predict the onset of shear-driven film separation from the surface at an expanding corner. The criterion is validated with experimental measurements of the percent of film mass separated as well as comparisons to other observations from the literature. The results show that the proposed force ratio correlates well to the onset of film separation over a wide range of experimental test conditions. The correlation suggests that the gas phase impacts the separation process only through its effect on the liquid film momentum.
M. A. Friedrich et al., "A Separation Criterion with Experimental Validation for Shear-Driven Films in Separated Flows," Journal of Fluids Engineering, American Society of Mechanical Engineers (ASME), May 2008.
The definitive version is available at http://dx.doi.org/10.1115/1.2907405
Mechanical and Aerospace Engineering
National Science Foundation (U.S.)
Keywords and Phrases
Film Flow; Flow Separation; Liquid films; Shear flow; Surface tension
Article - Journal
© 2008 American Society of Mechanical Engineers (ASME), All rights reserved.