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Proceedings of the Institution of Mechanical Engineers Part F: Journal of Rail and Rapid Transit [SJR: 0.449] [H-I: 21]
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Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0954-4097 - ISSN (Online) 2041-3017
Published by Sage Publications

[755 journals]

A comprehensive distributed architecture for railway traffic control using
multi-agent systems
- Authors: Hassanabadi, H; Moaveni, B, Karimi, M.
  Pages: 109 - 124
  Abstract: In this paper, we propose a Distributed Architecture for Railway Traffic Control using Multi-Agent Systems called DARTCMAS. It has a hierarchical organizational model that consists of three main layers of diverse agents: "Train Agents" at the bottom, "Station Agents" in the middle and "Center of Traffic Control Agent" in the top layer. Any train in the railway traffic system is considered as an intelligent agent that has reactive, proactive and interactive properties, simultaneously. DARTCMAS considers local traffic control centers that are embedded in some selected stations as "Station Agents". Lastly, "Center of Traffic Control Agent" acts as a comprehensive monitoring and supporting reference. We define an internal architecture for each of the agents. Furthermore, two types of interactions among agents are developed: first, inter-layer interactions that represent communications between two adjacent layers in the organizational model of DARTCMAS; and second, intra-layer interactions that represent relations between the same agents type in a specific layer. Simulations have been performed using MATLAB and the "Java Agent DEvelopment framework" whose results show the effectiveness of the model.
  PubDate: 2015-01-06T05:12:36-08:00
  DOI: 10.1177/0954409713503458|hwp:master-id:sppif;0954409713503458
  Issue No: Vol. 229, No. 2 (2015)
Experimental research on noise emanating from concrete box-girder bridges
on intercity railway lines
- Authors: Li, X; Zhang, X, Zhang, Z, Liu, Q, Li, Y.
  Pages: 125 - 135
  Abstract: Simply supported pre-stressed concrete box-girder bridges are the most common bridge type found on high-speed railway and urban rail transit lines in China. A field experiment has been conducted on the Pixian Viaduct of the Chengdu–Dujiangyan Intercity Railway, where two kinds of simply supported pre-stressed concrete box-girder bridges with a standard span of 32 m are used, one single track and the other double track. Characteristics of the noise underneath the box-girder, far from the bridge, and near the bridge gap were measured and analyzed in the time and frequency domains during high-speed train passage, as was the vibration of the box-girder’s bottom plate. The variations of noise with distance and train speed at locations 1.5 and 9 m above ground level were measured and fitted using mathematical formulae. A simplified formula to predict near-field bridge-borne noise was proposed and verified. The peak bridge-borne noise frequency and its tonal characteristic at 50 and 63 Hz for the double-track and single-track box-girders, respectively, were interpreted in terms of bridge vibration and sound radiation efficiency, respectively. The vibration/noise transfer function and coherence were evaluated, showing that vibration resonance is more significant than acoustic coincidence and that the former is more important in terms of noise reduction.
  PubDate: 2015-01-06T05:12:36-08:00
  DOI: 10.1177/0954409713503459|hwp:master-id:sppif;0954409713503459
  Issue No: Vol. 229, No. 2 (2015)
Experimental studies on the aerodynamic characteristics of a pantograph
suitable for a high-speed train
- Authors: Lee, Y; Rho, J, Kim, K. H, Lee, D. H, Kwon, H. B.
  Pages: 136 - 149
  Abstract: The aerodynamic properties of a pantograph that is under consideration for application on Korean high-speed trains are experimentally investigated. The selected experimental models were one-quarter scale pantographs (a double-arm pantograph, single-arm pantograph and a periscope pantograph) with either a rectangular panhead or a panhead with an optimized streamlined shape. To increase the performance and the robustness of the pantograph, the drag coefficient and the fluctuation of the lift coefficient along the angle of attack are simultaneously minimized. In order to confirm the aerodynamic enhancement of the pantograph due to the optimized panhead, the aerodynamic forces are compared with those of a pantograph with a rectangular panhead. To investigate the aerodynamic force distribution of a pantograph, the aerodynamic forces of the lift and drag of the pantograph are measured in wind tunnel tests and analyzed in terms of the pantograph’s components. In addition, wake flows are examined based on variations of the shape of the panhead.
  PubDate: 2015-01-06T05:12:36-08:00
  DOI: 10.1177/0954409713507561|hwp:master-id:sppif;0954409713507561
  Issue No: Vol. 229, No. 2 (2015)
Markov-based model for the prediction of railway track irregularities
- Authors: Bai, L; Liu, R, Sun, Q, Wang, F, Xu, P.
  Pages: 150 - 159
  Abstract: Irregularities in railway tracks are a key factor influencing the safety of trains. In this paper, rail track is considered to consist of consecutive track maintenance units whose individual defect states can be quantified in terms of a track quality index. A Markov stochastic process approach is used to evaluate the deterioration of a maintenance unit. A hazard model is formulated using the heterogeneity of the maintenance units, and a matrix of the Markov transition probabilities is constructed. The parameters of the developed models are estimated via a maximum log-likelihood function. The prediction model is validated with track irregularity data measured using track geometry cars.
  PubDate: 2015-01-06T05:12:36-08:00
  DOI: 10.1177/0954409713503460|hwp:master-id:sppif;0954409713503460
  Issue No: Vol. 229, No. 2 (2015)
Simulation of braking performance: The AnsaldoBreda EMU V250 application
- Authors: Pugi, L; Malvezzi, M, Papini, S, Tesi, S.
  Pages: 160 - 172
  Abstract: This paper presents the development of a modular tool for the prediction of train braking performance. Particular attention is devoted to the accurate prediction of stopping distances, considering different loading and operating conditions, necessary to verify safety requirements prescribed by the European Technical Specifications for Interoperability of High Speed Trains (TSI-HS) and the corresponding EN regulations. Results are verified by considering, as a benchmark, the AnsaldoBreda EMU V250: a European train being developed for Belgium and The Netherlands’s high-speed lines. Technical information and experimental data were available for this train, directly recorded during preliminary supplier exercise. Validation results were encouraging, and allowed a more accurate identification of the pad friction factor influence on braking performance.
  PubDate: 2015-01-06T05:12:36-08:00
  DOI: 10.1177/0954409713504394|hwp:master-id:sppif;0954409713504394
  Issue No: Vol. 229, No. 2 (2015)
Rail vehicle impact analysis: A critique of the suitability of the rigid
wall model and the assumption of symmetrical behaviour
- Authors: Xue, X; Robinson, M, Schmid, F, Smith, R.
  Pages: 173 - 185
  Abstract: This paper studies the accuracy of rigid-wall (stonewall) and symmetric models in rail vehicle impact stability. The investigation is based on modelling results and theoretical analysis. The theoretical investigation consists of a mechanical description of the conservation of energy transformation and instability of train impact due to irregular structural collapse and loose coupling patterns. It is shown that an unstable response is a common consequence in vehicle impacts and the corresponding stiffness amongst cross-sections has a strong effect on collapse stability. The modelling investigation summarises impact simulations of a cab vehicle. This illustrates the pitfalls of the rigid-wall and symmetric models as follows: firstly, using a rigid wall in modelling could mask irregular deformations and lead to overestimated crashworthy performance behaviours; and secondly, symmetric impacts could lead to asymmetric deformations resulting in crucial irregular responses of rail vehicles being missed. This paper explores the irregular responses of rail vehicles in train collisions and highlights the relevant issues which might be overlooked when conventional static approaches are used in dynamic scenarios. It is anticipated that the paper will provide increased insight into impact mechanics of rail vehicles and promote a rethink about the influence of characteristic behaviours in dynamic responses resulting in a more accurate representation.
  PubDate: 2015-01-06T05:12:36-08:00
  DOI: 10.1177/0954409713504393|hwp:master-id:sppif;0954409713504393
  Issue No: Vol. 229, No. 2 (2015)
A two-dimensional computational parametric analysis of the sheltering
effect of fences on a railway vehicle standing on a bridge and
experiencing crosswinds
- Authors: Sesma, I; Larraona, G. S, Vinolas, J, Rivas, A, Avila-Sanchez, S.
  Pages: 186 - 200
  Abstract: In a crosswind scenario, the risk of high-speed trains overturning increases when they run on viaducts since the aerodynamic loads are higher than on the ground. In order to increase safety, vehicles are sheltered by fences that are installed on the viaduct to reduce the loads experienced by the train. Windbreaks can be designed to have different heights, and with or without eaves on the top. In this paper, a parametric study with a total of 12 fence designs was carried out using a two-dimensional model of a train standing on a viaduct. To asses the relative effectiveness of sheltering devices, tests were done in a wind tunnel with a scaled model at a Reynolds number of 1 x 105, and the train’s aerodynamic coefficients were measured. Experimental results were compared with those predicted by Unsteady Reynolds-averaged Navier-Stokes (URANS) simulations of flow, showing that a computational model is able to satisfactorily predict the trend of the aerodynamic coefficients. In a second set of tests, the Reynolds number was increased to 12 x 106 (at a free flow air velocity of 30 m/s) in order to simulate strong wind conditions. The aerodynamic coefficients showed a similar trend for both Reynolds numbers; however, their numerical value changed enough to indicate that simulations at the lower Reynolds number do not provide all required information. Furthermore, the variation of coefficients in the simulations allowed an explanation of how fences modified the flow around the vehicle to be proposed. This made it clear why increasing fence height reduced all the coefficients but adding an eave had an effect mainly on the lift force coefficient. Finally, by analysing the time signals it was possible to clarify the influence of the Reynolds number on the peak-to-peak amplitude, the time period and the Strouhal number.
  PubDate: 2015-01-06T05:12:36-08:00
  DOI: 10.1177/0954409713504395|hwp:master-id:sppif;0954409713504395
  Issue No: Vol. 229, No. 2 (2015)
Experimental study of convective heat transfer at the surface of a rail
due to train passage
- Authors: Wang, M; Zhang, Y.-H, Bai, J, Wang, L.-B.
  Pages: 201 - 209
  Abstract: Frictional heat is generated when a train wheels pass over the rail. In addition heat is also generated by the use of an eddy current brake system. This generated heat causes a variation in the temperature of a rail’s surface; it accelerates the formation of both rolling contact fatigue and wear on the wheel/rail contact surface; and threatens the running safety of railway vehicles. The convective heat transfer characteristics on the surface of a rail when the train passes over it are very important in determining the temperature change of the rail. This paper reports experimental results of the convective heat transfer characteristics on a rail’s surface when a rolling wheel passes over the rail. A test model was created based on the configuration commonly used in a two-bogie car. The local and average heat transfer coefficients of the test section of the rail were obtained. The heat transfer results were extended to the real case using an analogy between the frequencies of the test wheel and train wheels. The results show that when the speed is less than 182 km/h, the intensity of convection heat transfer on the rail’s surface increases with an increase in the speed of the train, however, it decreases significantly when the speed is larger than 182 km/h.
  PubDate: 2015-01-06T05:12:37-08:00
  DOI: 10.1177/0954409713504567|hwp:master-id:sppif;0954409713504567
  Issue No: Vol. 229, No. 2 (2015)
Calculation and laboratory testing of the rotation resistance of a bogie
- Authors: Shi, H.-l; Wu, P.-b, Luo, R, Guo, J.-y.
  Pages: 210 - 219
  Abstract: The rotation movement between bogie and carbody is studied using vehicle system dynamics theory and formulas for the rotation resistance factor are derived for different air spring states. Laboratory tests are conducted and the obtained results are compared with calculations. The rotation resistance factor for motor and trailer cars experiencing AW0 and AW4 loading conditions when air springs are in inflated, deflated and over-inflated states are considered so as to validate the proposed formulas and test and discuss error sources. The rotation resistance factor of the bogie is related to the rotation angle and speed. The faster the rotation speed, then the greater is the rotation resistance factor. The greater the rotation angle, then the greater is the rotation resistance factor. The maximum rotation resistance factor is 0.094 for a trailer car at a rotation speed of 1 deg/s and experiencing AW0 loading conditions and with the air springs in the deflated state. The maximum rotation resistance factor when the air springs are deflated is much greater than that when the air springs are in the inflated state for a rotation speed of 1 deg/s. The maximum rotation resistance factor obtained at a rotation speed of 1 deg/s is much greater than the one obtained at 0.2 deg/s. The over-inflated state of air springs has little influence on the rotation resistance of the bogie. The calculated results obtained when considering air springs in inflated and over-inflated states are slightly smaller than test results with a maximum difference of 0.02. For the deflated state of the air springs, the calculated and test results for a trailer car are equivalent and the calculated results are slightly larger than the test results for a motor car with a maximum difference of about 0.02. The theoretical formulas should consider the dynamic nature of stiffness properties and damping effect of air springs. The effects of other suspension components should also be considered. A laboratory test or field test after assembly is an essential requirement. The comparison of test and calculated results validates the proposed formulas and allows sources of error to be discussed.
  PubDate: 2015-01-06T05:12:37-08:00
  DOI: 10.1177/0954409713508110|hwp:master-id:sppif;0954409713508110
  Issue No: Vol. 229, No. 2 (2015)