Boundary Layer and Wake Region Simulation for Low Reynolds Number Flows Around Bluff Bodies Using the Lattice Boltzmann Method

Two and three-dimensional flows around solid boundaries are interesting and important subjects to both scientists and engineers. Lattice Boltzmann Method (LBM) is a relatively new computational method to simulate fluid flows by tracking the collision, advection and propagation of mesoscopic fluid particles. LBM is originated from the Cellular automata combined with kinetic theory and the Boltzmann equation. The method solves the explicit finite difference scheme lattice Boltzmann equations which are second order in space and first order in time. LBM does not attempt to solve the Navier-Stokes equations directly, however, it obeys them. The two-dimensional flows around square and circular cylinders are simulated with uniform and nonuniform grid structures using LBM. The boundary-layer growth and wake region physics are captured with small scale details, and the results are discussed in comparison with the available references for Reynolds numbers between 50 and 350. The compatibility of the method to simulate a flow around ship-shaped geometries and a combination of objects is also provided.