The Research On Slit Flow Velocity Of Stable Moving Piped Carriage With Different Slenderness Ratios

In the commodity economy society,the transportation is the basic condition of human survival and social development.The economics of national growth is dependent on the transportation industry,but the traditional transportation will harm to the resource environment.Therefore,it is urgent to find a new way to meet people’s needs.The pipeline hydraulic transportation of tube-contained row materials is the mode of transportation in a new type of green resources,has advantages of area small,less polluted,low cost,low energy consumption and high safety.So it has a broad development prospect and high application value.In this dissertation,combined with the National Natural Science Foundation "research gap spiral pipe flow force characteristics(51109155)" and "train hydraulic pipeline transport energy research(51179116)",Shanxi Natural Science Foundation(2015011067),using Laser Doppler Velocimetry and homemade timer,experimental studies the slit flow velocity characteristics of stable moving piped carriage with different slenderness ratios.The resultsshowed that:1. The flow rate in the pipeline is three-dimensional,when the different slenderness ratios pipeline moved in the pipeline,this distribution will change;Compared with front and back section,the middle section slit flow velocity presents good regularity.Compared with the axial velocity,radial velocity and circumferential velocity flow velocity is small two orders of magnitude.2. When no pipeline car in the pipe,the axial velocity of slit flow in the test section shows a increasing trend from the pipe wall to the center.When the pipeline car moving in the pipe,the axial velocity of slit flow in the test section will have large change,and because of the different slenderness ratio,its distribution will also be different.Pipeline car length is 150 mm,from the pipe wall to the pipeline car wall slenderness ratio 0.33 type pipeline car axial velocity of slit flow shows a trend of decrease after the first increase;Slenderness ratio is 0.33,0.4,0.47,0.5 and 0.53 type pipeline car axial velocity of slit flow show a increasing trend again after first increases and then decreases.3. Under the same flow rate,the same slenderness ratio pipeline cars,as the change of transport load,scale model and the boundary,the three-dimensional velocity of slit flow will also produces change.Each section of the axial velocity,radial velocity and tangential velocity rule is not thesame,the axial velocity changed evidently,the radial velocity and tangential velocity changed feebly.4. Analyzed the relation of pipeline car velocity,pipe flow velocity and slit flow average velocity,and discussed the influence of slenderness ratios and transport load on the pipeline car velocity and slit flow average velocity.5. Through the standard regression coefficient method and SPSS software to analyze the influence factors of average slit flow velocity,and obtained the each factor influence degree.In this article,by combining slit flow with pipeline hydraulic transportation of tube-contained row materials,supplemented and improved the moving boundary slit flow theory,and provided a reference basis for pipeline car structure optimization.