Research On The Velocity Of Spiral Flow Caused By Hydrocyclone With Different Wrap Angle Of Guide

Due to its uniform suspension of silt and relatively high concentration and low velocity of solids,circular pipe cyclone transport is widely used in sediment removal and silting.The hydrocyclone is a device that converts the two-dimensional water flow in the pipe into a three-dimensional spiral flow by adding guide vanes in the pipe section to change the boundary of water flow.In this paper,the velocity of spiral flow caused by Hydrocyclone with different wrap angle of guide are studied by means of numerical simulation and physical test.The experimental conclusions are as follows:(1)The axial,tangential and radial velocity of water flow of the interior and outlet of the hydrocyclone of each section is symmetrical with respect to the rotation of 120° at the center of the section,and the circumferential and radial velocity is much lower than the axial velocity,and the radial velocity tends to 0 in most areas of the section.The inner part of the cyclone and its outlet are the middle area of the pipe(a circle with the center of the section as the center and the radius of about 25mm)with a small circumferential velocity and a large circumferential velocity near the pipe wall.That is to say,the area with a large spiral flow intensity is always close to the pipe wall,and the circumferential velocity is the maximum from 18 to 10 mmaway from the pipe wall.In most areas near the pipe axis,the axial velocity is largand the velocity gradient is small.In the areas near the pipe wall and guide bladethe axial velocity drops sharply and the velocity gradient is large.The radiavelocity is mainly affected by the guide blade.Due to the torsion of the guide bladafter entering the guide blade curved section,there is water flow towards the centeof the circle near the outer edge of the guide blade,and the radial velocity of wateflow gradually increases with the increase of the guide blade curvature.(2)The intensity and range of spiral flow generated when the guide blade envelope Angle is 5° and 10° are small.When guide blade envelop Angle is 12.5°,15°18.75° and 20°,the first wave peak reaches at Z=550mm,and it begins to decay around here.The larger the guide blade envelope Angle is,the greater the average circumferential velocity is,and the greater the average circumferential velocity is after the first attenuation.(3)According to the reverse curvature ?of guide and section maximum circumferential average speed m fitting curve obtained m cubic polynomial of?.When the torsion curvature of guide blade is greater than 0.6 °/cm,the increase trend of the maximum circumferential average velocity of the section slows down with the increase of the torsion curvature of guide blade.(4)The physical model test results are as follows.Facing the surface of the guide vane,the intensity of spiral flow near the wall of the guide vane is stronger than that near the guide vane.The water flow upstream of the trailing edge of the guide blade approaches the guide blade along the X-axis from the pipe wall,and its spiral flow strength gradually decreases and eventually approaches 0.The flow at the downstream of the trailing edge of the guide blade approached the guide blade along the X-axis from the pipe wall.The strength of spiral flow gradually decreased and then slightly increased,and the flow rotated from clockwise to counterclockwise.The research result of this paper is a beneficial supplement to the previous research work of cyclone and provides an important reference for further improving the research on the velocity characteristics of spiral flow generated by cyclone.