The influence of surface roughness on the hydrodynamics of the falling water film in cooling towers


This paper sets out the results of experiments for falling film at Rew = 70 ... 340 in the vertical channel of two coaxial tubes, ∅\varnothing∅ 37/17 mm, 1 m high, for a countercurrent air flow with Reair = 2200 ... 104. Subject to investigation was falling film on smooth and capillary-porous wall surfaces at constant film thickness greater than the height of the capillary-porous coating (0.3 mm). It was established that film thickness is weakly dependent on the velocity of the countercurrent airflow at w\ w w air = 1.7…7.3 m/s. The water concentration on a smooth surface is 2 times higher at the same film thickness. The results of flooding in a channel with a smooth wall surface confirm the validity of the Wallis equation with deviation up to 20%.

Author Biographies

Igor Kuzmenko, "Igor Sykorsky Kyiv Polytechnic Institute"
Heat Energy Faculty , APEPS department , docent
Alexandre Gourjii, "Igor Sykorsky Kyiv Polytechnic Institute"
Heat Energy Faculty , APEPS department , professor


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How to Cite
KUZMENKO, Igor; GOURJII, Alexandre. The influence of surface roughness on the hydrodynamics of the falling water film in cooling towers. Journal of Power Technologies, [S.l.], v. 100, n. 2, p. 152-160, june 2020. ISSN 2083-4195. Available at: <>. Date accessed: 23 july 2024.
Power Plant


falling film, countercurrent flow, capillary-porous wall surface, film thickness

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