RADIAL FLOW OF A THIN LIQUID FILM (1ST REPORT, LAMINAR-TURBULENT TRANSITION).

Abstract

This paper describes an experimental study of the laminar-turbulent transition in the radial flow of a thin liquid film on horizontal plane. The transition mechanism could be clearly observed in a visual observation using a stroboscope, since a turbulent motion in the thin layer of water disturbed the water surface. A sequence of experiments revealed the existence of a critical discharge Reynolds number, based on the equivalent length of opening, above which the transition takes place. The relation between Re and the dimensionless radius r//t* of the point of transition and the relation between r//t* and the local Reynolds number Rer based on the film thickness at r//t are established.