The Research On Numerical Simulation Of Flow Field For Regulation Engineering In Wuqiao Waterway

Wuqiao Waterway runs through Wuhan City,Which lies in the middle reach of the Changjiang River,begins,at Yangsimiao in Hanyang and ends at Wuhan Changjiang River Bridge,and it is a narrow straight waterway whose overall length is 5km.There is Baishazhou Waterway in the upper reach and Hankou Waterway in the lower reach.There are Baishazhou Shoal,Qianzhou Shoal,Huangwuli Side Shoal, Hanyang Side Shoal and Wuchang Deep Pool in Wuqiao Waterway,so the water flow there is very complicated and the navigation condition bad,which leads to many safety accidents as collision and threatens the safety of Wuhan Changjiang River Bridge.The current maintenance methods are dredging and changing for non-navigable spans as well as banning navigation for construction when the navigation obstruction becomes too serious,so it is very difficult to maintain the waterway,but no waterway regulation engineering is carried out yet.With the rapid development of national economy,the waterway condition of Wuqiao Waterway doesn't meet the development requirements of local economy,doesn't fit the reputation' Golden Waterway' for water transportation in Changjiang River,doesn't agree with the plan to make the middle reach of Changjiang River free and smooth and doesn't suit with the waterway regulation program for Changjiang River's Main Line.Wuqiao Waterway locates in particular position,around which there are many complicated water works including Wuhan Changjiang River Birdge flood protection works,ports,etc.Both the banks along the Changjiang River are protected by levees, and the section near Nianyutao on the right bank is the major dangerous section of construction engineering.The ports include Yangsimiao container terminal and Qingchuange pier on the left bank and Wuchang ferry terminal on the right bank. Other water works include the headwaters of Baishazhou water plant and Pinghumen water plant and Wuchang shipyard.The changes of water flow field in Wuqiao Waterway before and after the waterway regulation engineering will affect the safe navigation of vessels entering and leaving or passing through the waterway,and the normal function of surrounding water works,so it is quite necessary to simulate and analyze the flow field in Wuqiao Waterway before and after the waterway regulation engineering.The model CARDINAL is adopted,and the differences of water flow field before and after the waterway regulation engineering in Wuqiao Waterway under three different hydrological conditions(dry period,median water period and flood period) are simulated and analyzed in this paper.The numerical simulation of water flow field for waterway regulation engineering of Wuqiao Waterway in this paper is divided into 2-dimensional and 3-dimensional simulation.In the part of 2-D numerical simulation,the flow fields of the waterway under three engineering conditions(pre-engineering,post-engineering and engineering moving down 300m ) while under three hydrological circumstances are simulated and analyzed,and some sample points are set to analyze the changes of flow direction and velocity and velocity isolines,and also the cross-section velocity distributions and split ratio are verified;And in the part of 3-D numerical simulation,the flow fields of the surface layer and bottom layer after the engineering under three hydrological circumstances are simulated and analyzed,and also the changes of flow direction and velocity, velocity isolines and vertical distribution of related sample points are analyzed.The numerical simulation research of flow field for waterway regulation engineering in Wuqiao Waterway can offer reference information for safe navigation and course selection of vessels passing this area through analyzing the changes of flow field of mainstream before and after the engineering,can make us clear about the impact of the engineering on the navigation environment of Wuhan Changjiang Bridge through analyzing the changes of flow field in this area before and after the engineering,can make us clear about the silting condition of this area before and after the engineering and give reference information for dredging in this waterway through analyzing the size of slack water area(i.e.drying Up area during computation),can offer more accurate flow field information for ship maneuvering simulation in this waterway to increase its simulation precision.