The Wall Stress of the Capsule Surface in the Straight Pipe

As a clean, low-carbon, and green hydraulic transportation technology, wheeled capsule pipeline hydraulic transportation is a transportation mode conducive to the sustainable development of the social economy. Based on the method of a physical model experiment and hydraulic theory, the flow velocity characteristics in the pipeline when the wheeled capsule with a length–diameter ratio of 2.5 and 2.14, respectively, was transported in the straight pipe section with an inner diameter of 100 mm were studied in this paper. The results show that in the process of transporting materials, the flow velocity distribution of the cross section near the upstream and downstream section of the capsule was basically the same, and the axial velocity was smaller in the middle of the pipe and larger near the inner wall of the pipe. The radial velocity distribution was more thinly spread near the pipe wall and denser near the center of the pipe. The circumferential flow velocity was distributed in the vicinity of the support body of the wheeled capsule. For any annular gap section around the wheeled capsule, the radial velocity of annular gap flow was very small, and the average radial velocity of annular gap flow was about 1/30 of the average axial velocity of annular gap flow and about 0.7 of the average circumferential velocity of annular gap flow. The axial, circumferential, and radial flow velocities on the same radius measuring ring changed with the polar axis in a wave pattern of alternating peaks and troughs. These results can provide the theoretical basis for optimizing structural parameters of the wheeled capsule.

Section: Experimental Designmentioning

confidence: 99%

Section: Experimental Designmentioning

confidence: 99%

Study on Flow Velocity during Wheeled Capsule Hydraulic Transportation in a Horizontal Pipe

Li¹,

Gao²,

Sun³

et al. 2020

“…Asim [23] et al investigated the influence of the shape of a piped car on the flow field characteristics of a pipeline and determined the optimal shape of the piped car by comparing the flow field velocity and pressure distribution of the three different shapes of the designed piped car. Yang [24] et al used a combination of numerical simulation and physical experiments to analyze the distribution of the flow velocity and pressure around a piped car and to obtain the distribution law of shear stress on the wall of the piped car. Abushaala [25] et al studied a piped car in horizontal, vertical, and curved pipelines through numerical simulation to obtain the distribution law of water flow velocity and pressure around the piped car in various pipelines.…”

Section: Introductionmentioning

confidence: 99%

Research on the Characteristics of Flow Velocity of a Piped Car when Starting in a Straight Pipe Section under Different Loads

Lu,

Sun,

et al. 2024

It is of great significance to explore the flow velocity characteristics of piped cars when they are started under different loads. In this paper, the flow velocity characteristics of the water flow around a piped car when it is started in the straight pipe section are studied through physical experiments. The masses of the piped cars are 1.5 kg, 1.9 kg, and 2.3 kg, respectively. The results show that, with the increase in the load of the pipeline car, the axial flow velocity in the front section increases, the absolute values of radial flow velocity and circumferential flow velocity increase, and the gradient of flow velocity increases. The positive radial flow velocity and negative circumferential flow velocity regions increase, and the distribution of positive and negative radial flow velocities and circumferential flow velocities is obvious. The gradients of axial, radial, and circumferential flow velocities in the annular section all increase, and the contour spacing becomes smaller and more densely distributed. The absolute values of the radial and circumferential flow velocities increase. The regional demarcation of axial flow velocity in the rear section is more obvious, and the average value of axial flow velocity in the high-flow-velocity area behind the vehicle increases. Additionally, the gradient of flow velocity increases. The absolute values of radial velocity and circumferential velocity increase, the gradient of velocity increases, and the velocity distribution is obviously regional. This study supplements and improves the theoretical study of a piped car when it is started and has certain reference value for the research and application of the hydraulic transport technology of the barrel-loading pipeline.

“…With the steady improvement of social and economic construction, people's demand for the development of the transportation industry is increasing, but the environmental pollution caused by energy consumption and carbon emissions is also increasing [1]. In recent years, energy consumption and carbon emissions generated by the transportation industry have grown rapidly, which makes it one of the industries with high energy consumption and high emissions [2][3][4]. The proposal of the five national development concepts also reflects the national attention to green development [5].…”

Section: Introductionmentioning

confidence: 99%

Numerical Simulation of Flow Velocity Characteristics during Capsule Hydraulic Transportation in a Horizontal Pipe

Sun

et al. 2020

Self Cite

Capsule hydraulic transportation is a kind of low-carbon and environmentally friendly pipeline transportation technique. In this study, the flow velocity characteristics in the pipeline when the capsule is transported in a straight pipe section were simulated by adopting the RNG (Renormalization Group) k–ε turbulence model based on Fluent software and experimentally verified. The results showed that the simulated value of flow velocity in the pipeline was basically consistent with the experimental value during transportation of the material by the capsule, and the maximum relative error was no more than 6.7%, proving that it is feasible to use Fluent software to simulate the flow velocity characteristics in the pipeline when the capsule is transported in a straight pipe section. In the process of material transportation, the flow velocity distribution of the cross-section near the upstream and downstream sections of the capsule was basically the same, which increased with the increased length–diameter ratio of the capsule. The axial flow velocity was smaller in the middle of the pipe and larger near the inner wall of the pipe. From the inner wall to the center of the pipe, the radial flow velocity first increased and then decreased. The circumferential flow velocity was distributed in the vicinity of the support body of the capsule. The axial flow velocity of the annular gap section around the capsule first increased and then decreased from the inner wall of the pipe to the outer wall of the capsule. In the process of transporting materials, the influence of the capsule on the flow of its downstream section was greater than that of its upstream section. These results could provide a theoretical basis for optimizing the technical parameters of capsule hydraulic transportation.