We present an X-ray tomography study for the random packing of ellipsoids. The local structure displays short-range correlations. In addition to the contact number Z, we introduce ρshell, the average contact radius of curvature for contacting neighbors, as an additional parameter to characterize the local orientational geometry. In general, the local free volume w is affected by both Z and ρshell. We believe that the particle asphericity induces a polydispersity effect to influence the packing properties. A model is introduced which explicitly maps the ellipsoid packing onto a polydispersed sphere one, and it reproduces most of the experimental observations.

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Discontinuously electrified sections, such as neutral sections (NSs) widely exist in modern electrified railways. As a special arrangement of insulator, NSs with no electricity supplies are set up to ensure the two sections are kept electrically separate. This paper proposes a distance‐based mixed‐integer linear programming (MILP) model to incorporate both NS location planning and energy‐efficient train control (EETC) problem and concurrently optimise the NS location and train speed trajectory. The main contribution of this study is that based on the proposed integrated model, a number of case studies are conducted to investigate on the impact mechanism of NS locations on the total energy consumption of train operations. The optimisation results show that the energy saving rate in comparison with the worst cases is ranging from 1.9% to 6.1%% in various scenarios and significant saving rate can be achieved via planning the NS to be located in coasting areas as determined by EETC. In conclusion, the energy‐saving effect of the optimal NS location planning on the total energy consumption largely depends on how the NS‐triggered forced coasting is located in the journey and NS locations near stations and switching areas of speed limit lead to significant energy increase for bi‐directional journeys.

The dynamics force of iced-conductor is the driving force of galloping, its variation is depended on the aerodynamic character of iced conductor. The aerodynamic character of iced conductor is the key factor of galloping of iced-conductor, but the result of theoretically analysis and numerical simulation isn’t suited for the requirement of transmission line project. In the paper, basing on the theoretically analysis and numerical simulation, the simulation tests in wind tunnel of crescent-shaped iced conductor is stetted up and put into practice, and then the systemic study is carried into execution. The result of research is indicated that there is a better coherence between the numerical simulation and experiment test, and the result of numerical simulation is the beneficial supplement to the experiment test. The result can not only provide the original date for the galloping analysis, but also validate the affectivity of numerical simulation, support the research of mechanism and control of galloping.