Application Of Numerical Simulation Of Riverflow In Reconstruction Of Jiangdu West Sluice Bridge

Due to the need of urban construction in Jiangdu District of Yangzhou City,it is necessary to build a new west floodgate bridge in the west side of Jiangdu water conservancy project.The Jiangdu Water Conservancy Project is the source of the East Route of the South-to-North Water transfer Project and belongs to an important water conservancy project.As the new Jiangdu West Gate Bridge is close to the Jiangdu West Gate,after the bridge being built,the bridge backwater,the flow pattern under the bridge and the influence on the west gate of Jiangdu will be occurred.In this paper,the numerical simulation of the flow pattern in the reconstruction of the west sluice bridge is carried out by means of Delft3D software.The main contents of this paper are as follows.1.With the aid of commercial software Delft3D,a mathematical model of bridge hydraulics of Jiangdu West Gate Bridge is established.The model is from downstream of west gate in the east and out of water section in the east,west to lower reaches of Jinwan sluice,north to Mangdao floodgate and its south reaches the lower reaches of the junction between the west sluice waterway and the Mandao River.Its length from east to west and north to south is about 1600m.2.Using the established mathematical model,for four conditions of diversion to the west gate of Jiangdu and two drainage working conditions,the water level and velocity field in the calculated area without engineering are calculated respectively.It is the so-called calibration calculation.The calculated results are in good agreement with the actual situation.3.Using the established mathematical model,the six working conditions are studied.In the case of Jiangdu West Gate Bridge,the data of water level,increment of water level,velocity isoline,velocity increment isoline,velocity vector and vector of increment of velocity are calculated respectively.The results of the calculation are represented by computational domain global graph,the local map of the west gate,the local map of the confluence area and the local map of the bridge pier.It was concluded that the elevation of water surface and the velocity of flow in the bridge hole have been increased in the four conditions of water transfer and water supply.There is no effect on the flow of water under the two condition of flood discharge and waterlogging.4.Based on the established mathematical model,four conditions for diversion of water from the west gate of Jiangdu are studied and the original bridge and pier displacement scheme are compared.The coincidence of pier axis of bridge and pier axis of floodgate is still the best scheme for pier layout.It induces less transverse flow.