Flow Structures in Open Channels with Emergent Rigid Vegetation: A Review

On the edges of rivers where the flow velocity is low, aquatic plants flourish, with emergent rigid herbs being the most common. Since the flow structures of vegetated flow are strongly influenced by vegetation distribution patterns, homogeneous and heterogeneous canopies are defined based on the characteristics of vegetation distribution. A review summarizing recent advances in flow structures under the influence of different types of canopy arrangements, including ribbon-like homogeneous canopies, ribbon-like heterogeneous canopies, and patched heterogeneous canopies, is needed. Their flow development process, shear layer properties, coherent structure features, and momentum exchange characteristics are summarized, and a future research agenda for an in-depth understanding of the interactions between vegetation and flow is also highlighted.