Numerical Study of Efficient Condensation Characteristics on Tubes with Gradient Wettability Utilizing the LBM

The circular tube condensation is widely used in industrial production and scientific research. In the condensation process, the condensation heat transfer mechanism can be mainly divided into film condensation and drop condensation. The wettability of the surface plays a crucial role in influencing the condensation mechanism. Changes in surface wettability can lead to differences in the efficiency of heat transfer, which in turn affects the continued effectiveness of the condensation system. In this study, the condensation of circular tubes with different wettability characteristics and the dynamic evolution process of condensed liquid were studied, including the nucleation, growth, merging and separation stages of condensed droplets. The Lattice Boltzmann Method was utilized to simulate the condensation process under different wettability conditions. The dynamic evolution of condensed liquid and the change of heat transfer performance were studied. The gradient wettability circular tube was designed based on the bionic principle, which effectively improved the condensing characteristic of the circular tube, and the average condensation heat transfer coefficient was increased by 75.57%. The study revealed the influence rule of wettability on the condensation heat transfer efficiency, and provided theoretical support for optimizing the design of the condensation surface.