| At present,energy consumption,environmental pollution,and traffic congestion in transportation are all important transportation issues that the society pays attention to,and traditional transportation methods can no longer meet people's increasing transportation needs.The emergence of the hydraulic transportation technology of the striprel charging pipeline provides a new direction for the logistics transportation mode.This paper relies on the National Natural Science Foundation Project "Research on the energy consumption of hydraulic pipeline transportation of train(51179116)","the research on the hydraulic characteristics of the pipe crevice spiral flow(51109155)" and the Shanxi Natural Science Foundation Project "Research on the hydraulic characteristics of annular crevice spiral flow of the hydraulic pipeline transportation of tube loading(2015011067)".In this paper,the spiral flow velocity characteristics of the section of the double piped carriages' workshop with different guide strip angles were studied by using the method of theory and model test.The main conclusions are as follows:(1)In terms of axial flow velocity: Under different guide strip angles,the axial flow velocity distribution trend of each section of the workshop is basically show the distribution tendency of diffusion-contraction-rediffusion.The axial velocity in the water flow direction increases overall,the distribution tends to be uniform,and the range of the axial velocity value is more concentrated.The axial velocity value on the cross section of the vehicle support immediately behind the pipeline is extremely different;the same diversion strip is placed.Under angular conditions,the axial flow velocity along each section of the workshop increases in each flow rate interval and tends to be uniform;the measuring ring within a radius of 18 mm,the axial flow rate generally keeps small amplitude fluctuations,and the measuring ring with a radius greater than18 mm.With the increase of the angle of the polar axis,the peaks and troughs alternately appear and the peak value gradually decreases and tends to be a gentle change.(2)In terms of circumferential flow velocity: For the same section,with the increase of the angle of the guide strip,the circumferential flow velocitygradually increases in the positive direction,and the intensity of the circumferential flow velocity also gradually increases,with an increase of approximately 1m/s.The increase of the guide strip installation angle promotes the development of the circumferential flow velocity of the workshop section;under different guide strip installation angles,the columnar stacking diagram of the circumferential flow rate percentage of each section of the workshop is distributed in a stepped manner.The increase in the circumferential velocity is proportional to the relationship.The larger the angle of the diversion strip,the greater the proportion of the circumferential velocity distribution in the high velocity interval;section 1#(close to the support of the vehicle behind the pipeline)? section 3# at the same polar axis angle(75cm away from the support of the vehicle behind the pipeline),the circumferential flow velocity shows a trend of first decreasing,then increasing to the peak and then decreasing with the increase of the radius of the measuring ring,and with the increase of the placement angle of the guide strip,the circumferential flow velocity.The range of change increases overall;along the way,the circumferential velocity range on each measuring ring gradually decreases,and the circumferential velocity tends to be uniform and keeps the crests and troughs of the curve appearing alternately.(3)In terms of radial flow velocity: The 120-degree rotational symmetrical distribution of radial flow velocity along the water flow direction becomes increasingly apparent.Among the 3# section which is 75 cm away from the pipeline rear support and the 4# section which is 112.5cm away from the pipeline rear support.Obviously,the distribution of the section of the vehicle support near the pipeline and the section of the support near the pipeline are more turbulent;different from the trend of the stepwise growth of the columnar stacking diagram of the circumferential flow velocity distribution percentage,the stepwise growth trend of the radial flow velocity is not obvious.The radial velocity of the value decreases first and then increases along the direction of the water flow,that is,the radial flow of the workshop section changes from the direction of the center of the circle to the main direction,and then gradually changes to the direction of the center of the direction away from the center of the circle;when the placement angle of the guide strip increases.As the angle of the polar axis increases,the peaks and troughs of the radial velocity have anoverall offset on different polar axes,and the angle of the offset polar axis is about 30 °.(4)After the water flow increases,the axial velocity of each section of the workshop is promoted,the range of velocity values is expanded,and the change range of the axial velocity of the measuring point on different polar axes increases,the peaks and troughs are more obvious,as the diversion strip is placed.As the angle increases,the rate of change in the axial flow velocity is greater;the increase in the flow in the round tube makes the "velocity gap" of each section of the workshop more obvious,and the "velocity gap" along the flow direction also rotates counterclockwise in the positive direction.The rotation angle is approximately 120 °;the increase in flow rate makes the axial velocity curve in the section 75 cm to 150 cm away from the rear support of the pipeline more and more obvious with the increase of the polar axis angle.The research results in this paper enrich and perfect the theoretical study of the spiral flow of the pipeline,and provide a certain theoretical reference for the popularization and application of the hydraulic transportation technology of the striprel-filled pipeline. |
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