Experimental Study And Numerical Simulation Of The Flow Characteristics In Bending Reach

Almost there are some curves, in most rivers, estuaries and port zone. Research onthe flow characteristics of bending reach have an extremely important significance forbuilding and running river engineering, building port, designing river flood control,planning and designing of the bridge, planning basin and improving the navigationoperation.In this paper, using physical model test and numerical simulation method to studythe flow characteristics of bending reach. In terms of physical model tests, using theautomatic water level measurement system and the velocity measurement system tostudy water level and velocity changes of U-shaped bend channel. In terms of numericalsimulation calculations, based on physical model tests, a3D flow mathematical modelis set up by MIKE3software, which has the same size as the physical model size. Thismodel has been validated with the measured water level and flow velocity data ofphysical model test, the results showed that the calculated results agree with measureddata. So this model has been applied to calculate the flow characteristics of bendchannel flow.The results show that:(1) When the water flow come from the straight segment to curve segment, thewater level on the concave bank is rising and the water level on the convex bank isdropping. Water level difference between concave bank and convex bank performancefirst increases and then decrease. With the increased of water discharge, water leveldifference between concave bank and convex bank is increased. With the increased ofwater level, water level difference between concave bank and convex bank is decreased.(2) In the U-shaped bend channel, the flow velocity redistribution, the main streamline by the convex bank gradually towards the concave bank.(3) At the bottom, when the water flow through the U-shaped bend channel, themain flow direction tend to the convex bank. At the middle, when the water flow through the U-shaped bend channel, the main flow direction tend to be parallel with theborder. At the surface, when the water flow through the U-shaped bend channel, themain flow direction tend to the concave bank.(4) The flow velocity in the x and y directions in the vertical at the bottom to thesurface increased gradually. The flow velocity in the z directions in the vertical is shownthat the middle flow velocity in the z direction is greater than the bottom and surfaceflow velocity in the z direction at the concave bank, the middle flow velocity in the zdirection is less than the bottom and surface flow velocity in the z direction at theconcave bank.(5) Under the condition of the water level unchanged at the water outlet, with theincreased of water discharge, the flow velocity in the x, y and z directions betweenconcave bank and convex bank at the bottom, middle and surface are increased.(6) Under the condition of the water discharge unchanged at the water inlet, withthe increased of water level, the flow velocity in the x and y directions betweenconcave bank and convex bank at the bottom, middle and surface are decreased, theflow velocity in the z directions between concave bank and convex bank at the bottomand surface are decreased, the flow velocity in the z directions between concave bankand convex bank at the middle is decreased,...