Falling film characteristic numerical modelling and experimental validation

This paper presents a study on the falling film characteristics of vertical tubes and inclined plates, focusing on film thickness and wave frequency. A numerical modelling approach was employed using OpenFOAM’s InterFOAM solver to calculate the fluid dynamic characteristics of the falling film. The experiments were conducted using a variety of liquids, including water, ethylene glycol, and LiBr solution, and in the range of Reynolds numbers (Re) up to 1000. The film thickness was measured using two methods i. e., the contact point method and the holding method. Besides, a laser distance sensor was employed to detect the wave frequency of the falling film. The results indicated that the numerical model was able to accurately predict the mean film thickness in the complete turbulent film regime. The film thickness measured in this study was in the 0.3-1.0 mm range, with the average film thickness of the horizontal falling film being higher than that of the vertical falling film.
Research project PID2020-115837RB-I0 funded by MCIN/AEI/10.13039/501100011033. J. Zheng holds a China Scholarship Council Studentship with the Polytechnical University of Catalonia.
Postprint (published version)