Wake Interaction Using Lattice Boltzmann Method

Introduction

Fluids, such as air and water, are frequently met in our daily life. Physically, all fluids are composed of a large set of atoms or molecules that collide with one another and move randomly. Interactions among molecules in a fluid are usually much weaker than those in a solid, and a fluid can deform continuously under a small applied shear stress. Usually, the microscopic dynamics of the fluid molecules is very complicated and demonstrates strong in homogeneity and fluctuations. On the other hand, the macroscopic dynamics of the fluid, which is the average result of the motion of molecules, is homogeneous and continuous. Therefore, it can be expected that mathematical models for fluid dynamics will be strongly dependent on the length and time scales at which the fluid is observed. Generally, the motion of a fluid can be described by three types of mathematical models according to the observed scales, i.e. microscopic models at molecular scale, kinetic theories at mesoscopic scale, and continuum models at macroscopic scale. The lattice Boltzmann method (LBM) has found applications in fields as diverse as quantum mechanics and image processing, it has historically been and predominantly remains a computational fluid dynamics method. This is also the spirit of this book in which we largely develop and apply the LBM for solving fluid mechanics phenomena.