Study On Optimization For Sedimentat Effect Of Settling Basin In Chan River

With the hydrophilic landscape becomes more and more popular,more and more hydrophilic landscapes appeared in the rivers which flow through the city of the rivers.Many researches show that after construction of water landscape building in the river,the river sediment balance is destroyed,which will deposit large amounts of sediment in the reservoir area.By in the river built settling basin can reduce sediment carrying capacity of flow,and the sediment concentration in water is decreased,reducing the downstream of the reservoir sedimentation,to provide experience for the treatment of river sediment,which has important engineering reference value.Firstly,the basic equations,numerical methods and equations' discretion of hydrodynamic model(HD),the calculations of cohesive and non-cohesive sediment in mud model(MT)are introduced in detail.The method of calculating the shear stress of the bed surface at home and abroad is analyzed and discussed.Secondly,this paper used physical model experiment on the reservoir(rubber dam B#)to verify mathematical model,checking its reliability and rationality.To sink in the bunker on the right side of the main channel flow direction on the left,making use of the flow guiding and sand guiding role of spur-dikes.In the Chan River settling basin reasonable position,arranged the layout of the appropriate type and size of spur dikes.Finally,Through application of the mathematical model of the water to calculate sediment numerical simulation,according to the settling basin flow and two-dimensional sediment amount to analyze flow guiding and sand guiding effect,and combining settling basin at the end of the deposition amount to determine the reasonable spur dikes arrangement,making on the left side of the large sediment area to obtain the effective use,increasing sedimentation basin sediment deposition.Setting of spur dikes group,groins diversion sand guiding role changed the direction of water flow,the sediment is entrained to the left broad beach area,enlarged over water section of the flow velocity decreased,large amounts of sediment at here silting,which changes the original settling basin only owner channel occurred serious siltation and other position or no deposition thickness is very small,the embarrassing situation,the settling basin and most of the area has been effective use,sedimentation volume increased.Through analysis of the simulation results,it can be concluded that 120 degrees of spur dike flow guiding sand guiding effect better,less on the influence of local flow,flow pattern can quickly reach a state of uniform and stable and dam head erosion is small,so dam head silting thickness greater than other angles.In four conditions(120 degrees spur dikes are all arranged in the right bank)role,settling basin area on the left side has been effectively utilized,make more sedimentation in the region to the left.