Research On Flow Characteristics Of Bidirectional Inclined Vertical Axis Hydraulic Automatic Control Gate

Today,with emphasis on ecological environmental protection and efficient use of resources and energy,traditional gate stations with shortcomings such as cumbersome operations and the possibility of adversely affecting the ecological environment are no longer suitable for new needs,and vigorously developing new hydraulic self-controlling gates is new trends.The Bidirectional inclined vertical axis hydraulic automatic control gate is an innovation and improvement of the hydraulic automatic flap gate.Compared with other hydraulic automatic control gates,this gate has a simple structure,stable working conditions,and does not cause problems such as sedimentation and has good research value.The Bidirectional inclined vertical axis hydraulic automatic control gate has not yet been applied in actual engineering.Therefore,based on the analysis of the researches on the hydraulic automatic control gate in recent years at home and abroad,this paper uses a method of generalized physical model experiments to patent the utility model——the flow characteristics of the bidirectional inclined vertical axis hydraulic automatic control gate are studied,including the channel flow regime,water depth,velocity,the average dynamic water pressure at the channel floor and the dynamic water pressure at the gate plate.Finally,the empirical formula is used to calculate the flow coefficient of the bidirectional inclined vertical axis hydraulic automatic control gate to explore the influencing factors of the flow coefficient and the gate's over current capacity.The main research results are as follows:(1)Theoretical analysis shows that the weight of the bidirectional inclined vertical axis hydraulic automatic control gate G,the gate inclination angle ?,and the upstream water flow Q are the main factors affecting the degree of opening and closing of the gate.Based on the stress analysis of the gate,the force balance equation or moment equation of the gate under different incoming water conditions is established,and the working principle of the 5 cases of the gate and the maximum storage capacity of the gate in the closed state are obtained.The results show that when ?=45°,the gate has the maximum water storage capacity under its own weight.(2)Through model experiments,it was found that the bidirectional inclined vertical axis hydraulic automatic control gate has stable channel water flow patterns under different gate inclination angles and upstream design flow conditions,but the differences between theupstream and downstream are significant,resulting in the flow velocity,water depth,and time averaged dynamic water pressure at the upstream and downstream measurement points are quite different: the water surface before the sluice is calm,and the flow velocity,water depth and time-averaged dynamic water pressure distribution are more uniform;the downstream water flow shows a distinct rhomboid wave shape,and the flow velocity,water depth and time-averaged dynamic water pressure distribution are uneven,gradually becomes gentle as the water advances.The time-averaged dynamic water pressure distribution on the sluice plate is not uniform,and the pulsating pressure distribution on the sluice plate caused by the water flow calculated by numerical simulation is also not uniform.(3)The water-passing capacity of the bidirectional inclined vertical axis hydraulic automatic control gate gradually increases with the increase of the gate opening degree ?,and the gate opening degree is positively related to the gate inclination angle and the design flow;the larger the gate opening degree,the larger the relative opening of the gate hole e/H,the flow coefficient ?' of the gate decreases accordingly,and the flow coefficient is inversely related to the relative opening of the gate.The calculation results show that when ?=30°,the relative opening of the gate hole is the smallest and the flow coefficient is the largest.