Hydraulics and bedload in unsteady flow:Example of the Volga River  

作　　者：Gennadii Gladkov Viktor Katolikov Pakhom Belyakov Polina Rzhakovskaya Vitaly Zamyshlyaev 

机构地区：[1]Institute of Water Transport,Admiral Makarov State University of Maritime and Inland Shipping,Petersburg,198035,Russia [2]State Hydrological Institute,Petersburg,199106,Russia [3]Saint-Petersburg Research Center of the Russian Academy of Science,Universitetskaya nab.,Petersburg,199034,Russia

出　　处：《International Journal of Sediment Research》2024年第2期209-221,共13页国际泥沙研究（英文版）

摘　　要：The current paper deals with the navigable section of the Volga River tailwater of the Nizhny Novgorod Hydropower Plant.To ensure navigation in this area,the existing navigation structures are being reconstructed and an additional chamber of the Gorodets Navigation Lock is to be constructed,and an extended navigable channel in the Volga River is to be created.To assess the impact of the planned measures on hydrological and riverbed regimes,the hydromorphological situation has been analyzed,and the flow parameters and the water level regime in the tailwater pool of the hydro system have been studied.An analysis of the changes in the riverbed along the design channel path was done and the kinematics of the flow and sediment transport parameters were studied under conditions of unsteady water movement resulting from the daily regulation of the river flow.Numerical experiments have revealed the peculiarities of river sediment movement under conditions of unsteady water movement,and recommendations for modeling river bed deformation under such conditions have been developed.It was found that with daily and weekly regulation of river,discharge bedload transport becomes more active at the moment when a wave of daily release from the upper reaches of the hydrosystem passes through.The basic characteristics of bedload transport,i.e.,dune velocity and bedload rate,increase in comparison with a steady water flow.Under the conditions of unsteady water movement due to the daily regulation of the river flow,there are no strong changes in the size of the bottom dunes,while their velocity,and,consequently,the bedload rate increases significantly during periods when the wave of daily water releases from upstream passes.The results obtained indicate that for hydraulic calculations of the characteristics of water movement and sediment transport,it is necessary to use data from hourly observations of flow rates and water levels.It was found that during the passage of release waves under daily flow regulation,there are short periods

关 键 词：Riverine waterways Bedload transport Flow dynamics DUNES Froude number 

分 类 号：TV143[水利工程—水力学及河流动力学]