Introduction

The lattice Boltzmann method is introduced as a numerical framework for analyzing multiphase flows, nanoparticle transport, and inkjet printing processes. These systems require methods capable of handling complex interfaces, wetting behavior, particle motion, and multiscale interactions. After briefly discussing the limitations of conventional CFD approaches, LBM is presented as a mesoscopic method with advantages in boundary treatment, interfacial modeling, and parallel computation. Representative multiphase LBM models, including color-gradient, pseudopotential, and free-energy approaches, are also introduced. The discussion provides the conceptual background for the theoretical and application-oriented topics developed in the following chapters.