In this thesis, three-dimensional lattice Boltzmann multi-phase fluid model is applied to simulate binary fluid systems with large density ratio (1000) and partial wetting surface. It is based on the model of Zheng et al. [26] combined with partial wetting boundary condition of Briant et al. [12]. In the present work, a liquid droplet on a partial wetting surface with given contact angle is simulated for checking the reliability of model. The simulated results are in good agreement with theoretical solutions. In addition, two types of micro-structured surfaces which enhance surface hydrophobicity are also considered in the study. By applying appropriate implementation on micro-structures, the obtained apparent contact angles are also verified by experimental measurement and theoretical prediction with good agreement. Also, the parallel performance is discussed. The parallel efficiency can reach 80% when using 256 cores with a 2D domain decomposition.

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