Numerical Simulation Study on Hydraulic Characteristics of Square Platform Hollow Eco-Revetment Structure

The eco-revetment structure on river bank slopes plays a positive role in regulating nearshore water flow characteristics, enhancing bank slope stability, and providing a stable living environment for aquatic organisms. This study proposes an innovative eco-revetment structure—the square platform hollow eco-revetment structure. Ecological feasibility study through numerical simulation, analyzing the characteristic hydraulic movement patterns and flow movement mechanisms near the eco-revetment structure under different research parameters. The following conclusion can be drawn: the special design of openings on the side walls of the revetment structure increases the fluidity between water bodies, leading to complex water flow conditions near the revetment structure. Therefore, in the absence of plants, there are two large eddies inside the structure, as well as a “flow zone” opposite to the direction of external water flow. In the presence of plants, large-scale vortex structures are broken down into small-sized vortex structures, and the “flow zone” disappears. The distribution of flow characteristics is related to the research parameters. In the region where y/H ≤ 1, the velocity distribution is positively correlated with the inflow. There is a negative correlation between water flow velocity and porosity. The maximum values of turbulence intensity and Reynolds stress both occur at the top of the eco-revetment structure, and their distribution is positively correlated with the size of the side-wall openings and the inflow rate. The presence of plants leads to an increase in turbulence intensity and Reynolds stress, which diffuses into the interior of the structure. The impact of revetment structures on water flow determines the efficiency of material information and energy transmission and affects the stability of water flow ecosystems. Turbulent water currents can stimulate grass carp reproduction and increase the fertilization rate of fish eggs. The ratio of mixed-layer thickness to momentum thickness (tml/θ) is correlated with water flow velocity, and the presence of plants leads to an increase in tml/θ. This study provides ideas and methods for designing eco-revetment structures and constructing ecological rivers in the future.