The immersed boundary-lattice Boltzmann method for solving fluid-particles interaction problems

A new computational method, the immersed boundary-lattice Boltzmann method, is presented. This method is a combination and utilizes the most desirable features of the lattice Boltzmann and the immersed boundary methods. The method uses a regular Eulerian grid for the flow domain and a Lagrangian grid to follow particles that are contained in the flow field. The rigid body conditions for the fluid and the particles are enforced by a penalty method, which assumes that the particle boundary is deformable with a high stiffness constant. The velocity field of the fluid and particles is solved by adding a force density term into the lattice Boltzmann equation. This novel method preserves the advantages of LBM in tracking a group of particles and, at the same time, provides an alternative and better approach to treating the solid-fluid boundary conditions. The method also solves the problems of fluctuation of the forces and velocities on the particles when the bounce-back boundary conditions are applied. This method enables one to simulate problems with particle deformation and fluid-structure deformation. Its results are validated by comparison with results from other methods. (C) 2003 Elsevier Inc. All rights reserved.