Lattice Boltzmann model for shallow water flows in curved and meandering channels

Meandering channel flows are simulated using two-dimensional lattice Boltzmann models (LBM) for the shallow water equations. A boundary approach is designed for curved boundary treatment, which is applicable to no-slip, semi-slip and slip boundaries at a second-order accuracy. The large eddy simulation model is added in the lattice Boltzmann model, so that the turbulence can be taken into account and modelled efficiently. The model is verified by three numerical tests: the first two involve flows in meandering channels with 60 and 90 consecutive bends; the third is a 180 sharply curved channel. The numerical results are compared with available experimental data, showing good agreement. This provides a second-order accurate scheme for the LBM to simulate complex flows with curved boundaries.