Lattice Boltzmann Numerical Simulation of a Circular Cylinder

The lattice Boltzmann equation (LBE) model based on the Boltzmann equation is suitable for the numerical simulation of various flow fields. The fluid dynamics equation can be recovered from the LBE model. However, compared to the Navier-Stokes transport equation, the fluid dynamics equation derived from the LBE model is somewhat different in the viscosity transport term, which contains not only Navier-Stokes transport equation but also nonsteady pressure and momentum flux terms. The two nonsteady terms can produce the same function as the random stirring force term introduced in the direct numerical or large-eddy vortex simulation of turbulence. Through computation of a circular cylinder, it is verified that the influence of the two nonsteady terms on flow field stability can not be ignored, which is helpful for the study of turbulence.