In the past years, the Lattice Boltzmann Method (LBM) has been widely used by the scientific community as an alternative to the conventional numerical solvers for the Navier-Stokes (NS) equations. The present work in this thesis aims at studying the LBM for fluid dynamics. The main topics are concentrated in three aspects: the description of the model, the validation of this model, and the application of this model to an engineering case. In the first part the model is defined. Therefore, the Boltzmann equation and the Boltzmann distribution are defined. Also, the explanation of the framework where this method works is included. Then, the BGK-Approximation and the discretization of the Boltzmann equation are introduced. The algorithm needed to apply the model will also be explained together with numerical stability issues that one must take into account when it is implemented. An explanation of the different boundary conditions will also be summarized. In chapter 3 the LBM will be applied to different 3D cases to test its accuracy and validate the model. The Poiseuille and Couette flow will be studied and compared analytically. Lid driven cavity and the flow around an obstacle will also be simulated. In chapter 4, after the model has been validated, the LBM is used to simulate a complex situation to simulate the flow pattern in a lower plenum of a PWR reactor core, taking into account several simplifications, to understand the possibilities of the LBM implemented. To be able to perform chapter 3 and 4 an implementation in C++ has been developed.

Outgoing