Entrainment of air by a solid surface entering a liquid/air interface

✍ Scribed by W.L. Wilkinson

• Publisher: Elsevier Science
• Year: 1975
• Tongue: English
• Weight: 296 KB
• Volume: 30
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(75)85044-5

✦ Synopsis

The entrainment of air by a horizontal cylindrical roll rotating in a bath of liquid is considered. A simplified approach based on dimensionless analysis suggests that entrainment should occur at a critical value of the dimensionless capillary number, pU/u. Experiments on a range of viscous glycerol/water solutions and hydrocarbon oils indicate that this is so. The value of the critical capillary number is about 1.2 for all the fluid systems and this value is not sensitive to the angle of incidence of the surface.

This criterion could be of some value in a number of industrial coating processes.