Abstract: On the basis of research achievements in China and abroad, we made a review on the complex flow characteristics (flow velocity, shear stress distribution, eddy flow structure, turbulent kinetic energy, scale effect, separation zone, roughness coefficient and immersion ratio) near submerged river improvement structures (submerged groyne(dikes), vanes, cylindrical and beach-protection belt). We also discussed the mechanism of scouring and backwater effects. Research results indicate that the flow characteristics are determined by the disturbance of these submerged structures to flow. The induced eddy flow and backwater greatly affect the flow structure, increase local bed resistance, and redistribute the comprehensive roughness coefficient. Finally we present the shortcomings of the achievements and put forward prospects to future research.

Key words: submerged river regulation structures, submerged dike, flow characteristics, scour, backwater effect