Flow Regime Analysis Of Different Schemes For Lianshui Zhuma Sluice Demolition And Construction Project

Zhuma sluice(including Zhuma Yue sluice)is to the north of Zhuma town,about 5 km north of Lianshui County.It is the cascade control project of the main stream of Yanhe River and has the functions of drainage,water storage,irrigation and power generation.Due to the long time of construction and use,it needs to be rebuilt after being appraised by authoritative organizations.Based on the analysis of the characteristic water level and flow rate of the Yanhe River Basin and Zhuma sluice,a two-dimensional flow model of Zhuma sluice and its upstream and downstream rivers is constructed by using MIKE 21 software.The flow pattern of the flow through Zhuma sluice(sluice and power station)under different conditions is analyzed and studied.The calculation results provide a theoretical basis for the dismantlement and construction of Zhuma sluice.The main conclusions are summarized as follows:1.The hydrological characteristics of Yanhe River and its study area are calculated and analyzed.Designed discharge of Yanhe(Zhuma sluice)is 260.9m3/s once in 10 years.The design water level under Zhuma Gate is calculated according to the cross-sectional chart of Yanhe waterway regulation design and the design flow of main nodes along the line.The design water level is 6.19 m once in 10 years and 7.14 m once in 20 years.2.A two-dimensional plane flow model of Yanhe River and Zhuma sluice is constructed by MIKE 21 software.The upstream and downstream water level and velocity of Zhuma sluice are verified and calibrated by grid adjustment,terrain interpolation and roughness calibration.The results show that the calculated water level agrees well with the measured water level,and the velocity distribution of the calculated section agrees well with the measured value,which can reflect the objective law that the velocity of the main channel is larger and the velocity of the riparian land is smaller.The model can be used to calculate and analyze the flow pattern of Zhu-code sluice.3.The results of model calculation show that the original site layout of Zhuma sluice is better than that of upstream joint construction and sub-construction layout.The main manifestations are that the flow pattern of the original site layout is relatively smooth,which is conducive to the long-term stable operation of Zhuma sluice and the management of Zhuma sluice.The original site joint construction can be divided into sluice,power station symmetrical layout and asymmetrical layout.According to the calculation results,the symmetrical layout is more reasonable than the asymmetrical layout,but the symmetrical layout should pay attention to the bottom protection design of the downstream channel of the sluice,so as to prevent local scouring caused by excessive flow velocity and affect the safety of the Zhuma sluice.