The Dynamic Characteristics of a Piped Capsule Moving in a Straight Pipeline

Abstract

The hydraulic transportation of piped capsules is a new and energy-saving transportation mode, which is especially suitable for the long-distance and high-stability requirements of material transportation. In this paper, the COMSOL Multiphysics software was used to construct a mathematical model of the dynamic characteristics of a piped capsule moving in a straight pipeline, in which the boundary conditions were redeveloped, the inlet velocity distribution function was defined, and the physical experiment was carried out for verification. The dynamic characteristics were analyzed, and through the calculation of the energy consumption, the optimal piped capsule under the research conditions was obtained. The results show that the simulation results and experimental results for the piped capsule’s average moving velocity, axial velocity, and wall shear stress along the cylinder wall were basically consistent, with a maximum error of 14.22%, 2.62%, and 20.13%, respectively. With a decrease in the diameter-to-length ratio of the piped capsule, the axial velocity of the concentric annular gap flow decreased gradually. The area with a large shear stress was mainly concentrated at the front and rear ends of the cylinder wall, especially the rear area of the support feet of the piped capsule. With the increase in the diameter of the piped capsule, the wall shear stress of the capsule increased. Finally, the superior diameter-to-length ratio for the piped capsule under the research conditions was obtained and shown to be ε = 0.4. The research in this paper will provide a theoretical reference for the structural design and dynamic mechanism analysis of the piped capsule.