Study On The Influence Of Vertical Guide Wing On Hydraulic Characteristics Of Bend Flow

In water resources projects,due to the limitation of topography and geology,it is necessary to set up bends.Under the combined action of centrifugal force and gravity,the flow regime deteriorates and the bends structure is destroyed.Therefore,in order to improve the flow regime in the bends,this paper proposes to set vertical guide wings on the concave bank of the bends.Some characteristics of the vertical guide wing are similar to those of spur dikes,but in comparison,the vertical guide wing faces the water surface relatively along the water flow direction,and has less blocking effect,which can reduce the local water damage caused by spur dikes,and has the advantages of simple structure and obvious improvement effect on the water flow regime.At present,there is little research on the vertical guide wing,especially the research on the influence of vertical guide wing parameters on the hydraulic characteristics of bend flow.Based on this,the method of combining model test with numerical simulation is adopted,this paper studies the influence of vertical guide wing on bend flow structure and vertical guide wing parameters on bend flow hydraulic characteristics,and briefly analyzes the application of vertical guide wing to bend flow and discharge.The main research contents and achievements are as follows:(1)The influence of vertical guide wing on the flow structure in bends is studied,and the feasibility of vertical guide wing is verified.The results of flow regime,water surface line,velocity and loop circulation before and after setting vertical guide wing are analyzed.The results show that with the vertical guide wing,the fluctuation range of water flow in the downstream section of the bends is smaller,the water surface is more stable,the velocity distribution is more uniform,the area of high velocity zone is greatly reduced,and the bends circulation can be effectively reduced.Therefore,the vertical guide wing can obviously improve the water flow in the bends.(2)The influence of dimension parameters of vertical guide wing on hydraulic characteristics of bend flow is studied.The dimensional parameters include: the length B1 of the vertical guide wing facing the water surface and the length L of the vertical guide wing in the direction orthogonal to the wall surface.The results show that the longer the water-facing length B1 of the vertical guide wing,the higher the degree of water flow relative to the direction of water flow,the smaller the blocking effect,the smaller the local disturbance intensity,and the smaller the local scouring effect on the vicinity of the vertical guide wing.However,on the whole,the sensitivity of the curved water flow to the water-facing length B1 of the vertical guide wing is not high.The water flow in the bends is sensitive to the length L perpendicular to the wall surface.In a certain range,the longer L is,the more uniform the water surface in the downstream of the bends,the smaller the area of high velocity zone,and the more stable the flow regime.(3)The influence of the number parameters of vertical guide wings on the hydraulic characteristics of bend flow is studied.The water flow situation in the bends is analyzed when one,two and three vertical guide wings are respectively arranged in the bends section.The results show that when two vertical guide wings are set,the water surface at the outlet of the bends and the downstream direct current section is more stable,and the effect of improving the flow regime is better.(4)The influence of vertical guide wing position parameters on the hydraulic characteristics of bend flow is studied.Position parameters include: single vertical guide wing position and double vertical guide wing position.The results show that when the single vertical guide wing is set at 22.5,the flow regime is obviously better than that when the vertical guide wing is set at 11.25 upstream and 33.75 downstream of the bends.When the double vertical guide wings are arranged at 11.25 upstream and 33.75 downstream of the bends,the water flow regime is obviously better than the scheme that the double vertical guide wings are arranged in the first half of the bends or the second half of the bends.(5)The application of vertical guide wing to bends and flow is studied.The results show that the vertical guide wing can be applied not only to the small curvature curve of 45,but also to the large curvature curve of 90,and the flow rate can be widely applied.