| At present,the logistics transportation has become an important issue of social concern,the traditional mode of transport has been unable to meet people’s growing transport needs,also showed some disadvantages,such as transportation energy,environmental pollution problems,traffic problems,etc.The emergence of tube feeding pipe hydraulic transportation technology provides a new direction for the logistics mode of transportation,which has many advantages such as small land occupation rate,clean,etc.This paper relies on the National Natural Science Foundation Project of China,"The study of hydraulic characteristics of pipeline gap spiral flow(51109155)" and "Shanxi Natural Science Foundation Project(2015011067)",adopt the method of combining theoretical analysis and experimental research,the experiment design flow rate Q is 40 m3/h,the load is 900 g,under the conditions of the Lx D for the 100mmx70 mm,150mmx60mm,150mmx70 mm three kinds of pipeline models,research gap spiral flow velocity characteristics with different guide vanes installing angles,The main conclusions are as follows:(1)No matter what kind of piped cars in the pipeline running,will break the original flow state of the concentric distribution of axial velocity,the maximum axial velocity from the tube center moved to the tube wall;The gradient of axial velocity in the cross-section of piped car is smaller than the after cross-section of piped car and the front cross-section of piped car.Under the same conditions,the axial velocity of the gap spiral flow formed when the piped car is 60 mm in diameter is larger than the average velocity of the pipeline flow,and the axial velocity of the gap spiral flow formed when the piped car is 70 mm in diameter is less than 60 mm in diameter of the piped car.(2)With the increase of the installing angle of guide vanes,the axial velocity of the gap spiral flow in the after cross-section of piped car and the front crosssection of piped car are decreased first and then increased and then decreased and then increased,which is basically W-type distribution;The cross-section of piped car increases.The variation range of the axial velocity of the gap spiral flow in the after cross section is increases with the increase of the installing angle of guide vanes;The axial velocity distribution of the gap spiral flow in the cross section of piped car is basically concentric and the maximum axial velocity was in the ring measurement about the location of the 44 mm;the maximum axial velocity of the gap spiral flow in the front cross-section of piped car no longer show the form of mutation with the increase of the installing angle of guide vanes.(3)With the increase of the installing angle of guide vanes,the radial velocity of the gap spiral flow in the after cross-section of piped car is increased first and then decreased and then increased,which is basically N-type distribution;the radial velocity of the gap spiral flow in the cross-section of piped car is basically stable in the 0-0.04m/s;the radial velocity of the front cross-section of piped car is basically M-type distribution,which is increased first and then decreased and then increased and then decreased.The maximum radial velocity of the gap spiral flow in the after cross section of piped car increases first and then stabilizes at 0.5 m/s to 0.6 m/s with the increase of the installing angle of guide vanes;The radial velocity of the gap spiral flow in the cross section of piped car is basically not changed with the change of the installing angle of guide vanes;The minimum radial velocity of the gap spiral flow in the front cross section of piped car appeared in the 90 o,210o,330 o.(4)With the increase of the installing angle of guide vanes,the circumferential velocity of the after cross-section of piped car is N-type distribution,which is increased first and then decreased and then increased;the circumferential velocity of the cross-section of piped car is shows a linear growth trend;the circumferential velocity of the front cross-section of piped car is Mtype distribution,which is increased first and then decreased and then increased and then decreased.No matter what kind of the guide vanes installing angles conditions,The maximum circumferential velocity of the gap spiral flow in the after cross section of piped car generally appear in 120 o,240o;with the installation of guide vanes and the installation angle increases,The circumferential velocity of the gap spiral flow in the cross section of piped car the car is more and more similar to the concentric distribution,and the maximum is larger.On the same polar axis in the cross section,the circumferential velocity of the same measuring point increases with the decrease of the radius of the measuring ring.The variation range of the circumferential velocity of the gap spiral flow in the front cross section is increases with the increase of the installing angle of guide vanes.(5)No matter what kind of piped cars,the average axial velocity of the piped cars and the average axial velocity of the gap spiral flow gradually tend to the average velocity of the pipeline flow.The axial running velocity of the piped cars are increasing with the increase of the installing angle of guide vanes.Among them,the increase of the 100mmx70 mm piped car is the maximum(0.1999m/s),and the increase of the 150mmx70 mm piped car is the smallest(0.114m/s). |
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