Numerical simulation of falling film thickness around a horizontal tube

A numerical study of liquid falling film outside a horizontal tube is performed by establishing a mathematics physics model.And the simulation results fit well with the experimental ones.The film thickness and the film distribution at different Reynolds numbers are computed to analyze the influence of structural and flow parameters on the film thickness and the film distribution.The experimental results show that the film thickness increases with the film Reynolds number increasing.The film thickness around the tube firstly decreases,and then increases at a certain Reynolds number.The film thickness decreases with the increase of the tube pitch,and with the increase of the Reynolds number the film becomes more fluctuated and dryout region easily appears.