Author(s): Wanyun Xue; Shiqiang Wu; Xiufeng Wu; Jie Zhou; Jiangyu Dai
Linked Author(s): Wu Shiqiang
Keywords: Laboratory experiment; Large-eddy simulation(LES); Vegetation patch; Coherent structures
Abstract: A number of Large-eddy simulation studies on flow in a rectangular open channel blocked with an artificial submerged rigid vegetation patch have focused on the effects of the coherent structures on momentum transfer across the vegetat ion edge. The Finite Difference Method (FDM) with Fractional Area/Volume Obstacle Representation (FAVOR) method and Volume of fluid (VOF) algorithm was used to solve the filtered Navier-Stokes equations on a Cartesian non-uniform grid. The computed results compared well with experimental measurements. Computational results provided insight into the spatial evolution of coherent structures and the monami phenomena, and coherent structures (vortices) gave velocity time series a strong periodic signature. An intermittent low-speed streak, another characteristic of turbulent boundary layer, also occurred at the vegetation edge, when partial vegetation is present.