Artificial floating bed (AFB), as a novel type of ecological drainage ditch, is extensively used worldwide. To more effectively design the structure of the project, an accurate velocity model is required. In this study, a two-dimensional Lattice Boltzmann method (LBM) is employed for the simulation of the vertical velocity in a channel with AFB. The large eddy simulation (LES) is conducted to simulate turbulent flows, while the drag force of AFB is discretized with a centered scheme. Two sets of experimental data were used to verify the model, the mean value of root mean square error (RMSE) and coefficient of determination (R2) are 0.93 and 1.84, respectively. It proved that the proposed model is more effective to simulate the vertical velocity in a channel with AFB.
The innovation of this paper is the discretization of N-S equation in LBM form under the action of AFB.
LBM is more conducive to simulate complex boundary problems, and more complex conditions (such as vegetation root of AFB) can be added to it.
The water structures also play an important role in the transport of sediment and nutrients, and LBM method can be easier to reflect the water structures and combine with transport of sediment and nutrients.