Numerical simulation of velocity distribution and pollution retention in flexible submerged vegetated channel

Abstract

Vegetation is an important factor that affects the hydrodynamics of river channels. Using hydrodynamic and water quality models in vegetated channels can help better understand the problem of river water pollution. In this paper, the lattice Boltzmann method (LBM) is used to simulate the hydrodynamics of flexible vegetated channels, and the projected area characteristics of flexible vegetation are input into the model to obtain better simulation results for the vertical velocity distribution. At the same time, the random displacement method is used to simulate the transport law of pollutants and calculate the pollutant retention rate under different vegetation projected area characteristics. The results show that both vegetation species and average flow velocity have significant effects on pollutant retention efficiency. This method helps to optimize the selection of species, density, and distribution of river vegetation.