STUDY OF THE HYDRODYNAMICS OF THE LIQUID FILM FLOW ON A VERTICAL SURFACE WITH LONGITUDINAL FINNING

Authors

DOI:

https://doi.org/10.20535/1813-5420.4.2019.207097

Keywords:

liquid film, longitudinal finning, minimum irrigation density, contact angle, intensification of heat and mass transfer processes

Abstract

The features of the flow of a liquid film on a vertical surface with longitudinal ribs are considered. The forces that are present in the liquid film in the absence of interfacial friction between the liquid and the gas medium are analyzed. Dependencies are obtained that describe the shape of the surface of the fluid in the space between fins. It was shown that when the irrigation density is greater than the minimum at which the finned surface is guaranteed to be completely wetted (the minimum film thickness in the middle between the fins is greater than zero), the surface of the liquid film has a shape with smooth curvature. Depending on the specific transverse geometric dimensions of the pipe, the ribs and the gaps between the ribs, the surface of the liquid can have either a concave or convex shape. The results obtained make it possible to determine the boundary conditions on the interphase surface (liquid - gas), which are necessary for analytical and experimental studies of hydrodynamics and heat and mass transfer during fluid flow along a vertical fin surface.

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Published

2020-03-05

Issue

Section

ENERGY EFFICIENCY AND ENERGY SAVINGS