Numerical Simulation Of Flows Using Lattice Boltzmann Method

Lattice Boltzmann method (LBM) is studied in this dissertation for solving fluid flow problems. The basic concept of the method is firstly described, and its history of development is briefly reviewed. In order to solve the viscous flow problems which are governed by the macroscopic Navier-Stokes Equations, a detailed investigation including the principle and application of LBM is presented.When the flow problems are solved by LBM, the particle velocity model is usually required to accomplish the simulation. Therefore two particle velocity models named as D2Q9 and D2Q13 are firstly analyzed and compared, and then they are implemented in the framework of LBM to simulate 2D lid driven cavity flows; as the uniform grid is used by the traditional LBM, it encounters difficulties when dealing with complicated configurations represented by curved boundaries. In order to overcome this difficulty, a new method named as TLLBM which uses non-uniform grid is proposed. The new method is applied to solve the flows over a cylinder and NACA0012 airfoil in the present work; Furthermore, some popular models for LBM are described in the dissertation, and special attention is paid to the IEDDF thermal model that is implemented to simulate 2D cavity nature convection flows.A comparison between the numerical results and the reference works is made, and they agree well with each other.