Numerical Simulation To Energy Dissipation Process Of The Ladder Leaves Turn Spiral Flow Energy Dissipation Devices

In the process of the Pressure pipeline water transportation betweentwo places which has long distance．the excess energy of the project will leadto a seris of problems.So how we can slove them in one economic and effectiveway.scientific research workers have studied in-depth energy dissipation ofexcess pressure water head.it is widely accepted to install a Spiral flow energydissipation device in the pipe.at the same time, the device has been applied tothe indus-trial, agricultural and domestic water. But water with spiral flow isbelong to aty-pical linear flow.however, in the process of testing device, the lackof the precision of the measuring instrument,experimental methods, the limitof uncertainty p-arameter of test equipment will lead to the difference of the testresults, Maybe some result are contradictory. The characteristic of spiral flow inthe process of flowing is very complex,the eddy current will be produced in thecase of conditions.The innate spiral flow device is to convert mechanicalenergy into heat energy as much as possible, at last the excess energy will bereduced. However, the analytical method of the test and the test data have notbeen able to meet the actual needs of the project, so it is helpful to the practical engineering of the spiral flow unless we must study of energydissipation mechanism more in-depth.The numerical simulation calculation wasbuilt on the basis of the device’s experimental study.the specificenergy dissipation process of energy dissipation device will be understood bythe numerical simulation calculation.In this paper, spiral flow energy dissipation device physics model isbuilt by the pre processor-GAMBIT of the FLUENT software.when we useSIMPLE flow field numerical method,we need make the finite volume methodto achieve the discrete equations, k-εmodel will be used as the model ofturbulence. the boundary condition of inlet and outlet is stressful. The approachof wall is near wall function.in order to test the feasibility of numericalsimulation to the keystone turn leaves spiral flow energy dissipation.so we needset up seven points as the same as then on the device which has been studied.We can get some conclusions through numerical simulation.such as the date ofthose points,the picture of flow lines to different sections;the velocity vectorand temperature changes schematic; the pressure distribution of different crosssections;the dates of turbulence intensity and axial, radial and the tangentialvelocity and so on.At last.we re-use some kinds of software including TecPlot,EXCEL to handle the resulting data for further processing.Some conclusions can be achieved by analysing the results of thenumerical simulation of the energy dissipation device.such as:(1) trapezoidaldesign leaves turn spiral flow energy dissipation device is reasonable;(2) the main area of energy dissipation devices in turn leaves the trapezoidal hole afterthe board energy dissipation mechanism;(3) energy dissipation devices andspeculation same;(4) device is a helical flow attenuation characteristics ofthree-dimensional rotating spiral flow, tangential velocity variation follows theexponential equation;(5) the excess energy is converted to internal energy, cancause the temperature inside the fluid increases, the last way to dissipate heat,consistent with speculation;(6) changes in cross-sectional area over the water,swirl fluid produced can consume large amounts of energy;(7) in the same flowrate, the twist angle is constant, the pressure on the front wall of the orifice platewill decrease with the increase of the opening angle;(8) at the same flow rate,the twist angle is constant, in front of the wall plate suffered pressure willdecrease with the increase of the opening angle;(9) secondary vortex wasproduced when the area of pipeline increases.