韩江高陂水利枢纽过鱼设施多尺度协同优化水力模型试验研究与应用OA

To ensure unimpeded migration pathways for the Class II nationally protected species Anguilla marmorata(Marbled Eel)and semi-migratory fish species like silver carp(Hypophthalmichthys molitrix)and bighead carp(Aristichthys nobilis)(with critical swimming speed≤1.0 m/s)downstream of the Hanjiang Gaobei Hydro Project,this study constructed a multi-scale(1∶4 for fishway sections,1∶10 for the entire fishway,and 1∶85 for the entire project)normal hydraulic physical model based on Froude similarity criteria.A coordinated optimization methodology termed the"Four Adjustments"was proposed:adjusting structure(optimizing the size combination of baffle orifices),adjusting flow pattern(improving flow regime and velocity distribution),adjusting layout(modifying the position and form of inlets/outlets),and adjusting inlet(creating a low-velocity zone).Through optimizing baffle orifice sizes,adding a mid-level water intake,installing energy-dissipating piles to reduce inlet velocity,and optimizing outlet operation management,key issues in the baseline scheme were successfully resolved.These issues included poor hydraulic connectivity within the fishway,mismatch between inlets/outlets and water levels,and excessively high inlet velocity(>1.7 m/s).Model tests and operational monitoring in 2023 confirmed that post-optimization,the maximum velocity at key orifices within the fishway was≤0.84 m/s with smooth flow.A low-velocity activity zone(<1.0 m/s)formed in the inlet area,significantly enhancing the upstream passage efficiency for various fish species(including target juvenile fish),achieving a daily net upstream passage of approximately 328 individuals.The methodology system established in this study,based on multi-scale physical model testing and the coordinated"Four Adjustments"optimization,can provide an effective technical reference for the design optimization and operational management of efficient fish passage facilities in large-scale hydro projects.