  The immersed boundary lattice Boltzmann method (IB-LBM) has been widely used
in the simulation of fluid-solid interaction and particulate flow problems,
since proposed in 2004. However, it is usually a non-trivial task to retain the
flexibility and the accuracy simultaneously in the implementation of this
approach. Based on the intrinsic nature of the LBM, we propose a simple and
second-order accurate IB-LBM in this paper, where the no-slip boundary
condition on the fluid-solid interface is directly imposed by iteratively
correcting the distribution function near the boundary, markedly similar to the
treatment of boundary condition in the original LBM. Therefore, there are no
additional efforts needed to construct an interfacial force model (such as the
spring, feedback and direct force models) and absorb this force into the
framework of LBM. It is worth mentioning that we retain the discrete delta
function for the connection between the Lagrangian and Eulerian meshes, thus
preserving the flexibility of the conventional IB-LBM. Second-order accuracy of
the present IB-LBM is reasonably confirmed in the simulation of cylindrical
Couette flow, while the conventional approach is generally a first-order
scheme. The present method is first validated in the flow past a fixed
cylinder. No streamline penetration is found, indicating the exactly
enforcement of the no-slip boundary condition. Furthermore, in the simulations
of one and two particles settling under gravity, good agreements can be
observed comparing with the data available in the literature.
