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

[737 journals] [SJR: 0.449] [H-I: 21]

Full-scale measurement and analysis of train slipstreams and wakes. Part
1: Ensemble averages
- Authors: Baker, C. J; Quinn, A, Sima, M, Hoefener, L, Licciardello, R.
  Pages: 451 - 467
  Abstract: This paper describes a series of extensive and unique full-scale measurements of the slipstreams of trains of various types that were carried out as part of the EU-sponsored AeroTRAIN project, together with the analysis of the experimental data. These experiments were carried out with the fundamental aim of seeking to reduce the complexity of the current technical specifications for interoperability (TSI) testing methodology. Experimental sites in Spain and Germany were used, for a range of different train types – high-speed single-unit trains, high-speed double-unit trains, conventional passenger units and locomotive/coach combinations. The data that was obtained was supplemented by other data from previous projects. The analysis primarily involved a study of the ensemble averages of the slipstream velocities, measured both at trackside and above platforms. The differences between the flows around different train types were elucidated, and the effect of platforms on slipstream behaviour described. A brief analysis of the effects of crosswinds on slipstream behaviour was also carried out. Through a detailed analysis of slipstream velocity components, the detailed nature of the flow around the nose and in the near wake of the train was investigated, again revealing differences in flow pattern between different trains. Significant similarity in the far wake flows was revealed. These fundamental results form the basis for the detailed discussion of the proposed TSI methodology that will be presented in Part 2 of this paper. Overall the results enable the nature of the flow field around trains to be understood in far greater detail than before, and also allow the developments of a revised TSI methodology which is more efficient than current practice.
  PubDate: 2014-06-06T00:09:11-07:00
  DOI: 10.1177/0954409713485944|hwp:master-id:sppif;0954409713485944
  Issue No: Vol. 228, No. 5 (2014)
Full-scale measurement and analysis of train slipstreams and wakes. Part 2
Gust analysis
- Authors: Baker, C. J; Quinn, A, Sima, M, Hoefener, L, Licciardello, R.
  Pages: 468 - 480
  Abstract: Part 1 of this paper reports results from the extensive full-scale slipstream measurements carried out as part of the AeroTRAIN project, and in particular concentrates on the ensemble analysis of this data. This paper concentrates on the analysis of maximum gusts, in order to make suggestions for modifications to the current technical specifications for interoperability (TSI) methodology. The very large data set obtained for one particular high-speed train type (the S-103) enabled the variation of slipstream gusts with vehicle speed and wind speed to be determined. It was also possible to carry out a statistical analysis of the gusts that enabled the standard uncertainty of the TSI gust parameter to be determined. It was shown that for most trains the maximum gusts occurred in the near wake of the train, but for double-unit trains the maximum gusts could occur around the gap between the units and for locomotive/coach combinations the maxima could occur around the nose of the locomotive or at the discontinuity between the train and the locomotive. Perhaps the most significant result, which could allow a considerable simplification of the TSI methodology, was that if both trackside and platform measurements for a particular train were plotted against height above the rail, then, with very few exceptions, they fell onto one curve, which implies that a trackside measurement could replace the current required platform measurement.
  PubDate: 2014-06-06T00:09:11-07:00
  DOI: 10.1177/0954409713488098|hwp:master-id:sppif;0954409713488098
  Issue No: Vol. 228, No. 5 (2014)
Development of effective performance measures for wayside rail curve
lubrication in heavy haul lines
- Authors: Uddin, M. G; Chattopadhyay, G, Rasul, M.
  Pages: 481 - 495
  Abstract: Rail curve lubrication using wayside gauge face lubrication systems is widely used by the railway industry. It provides cost-effective solutions to reduce rail/wheel wear, energy consumption, costs and noise. Research efforts on cost-effective friction management solutions for the Australian heavy haul industry have been limited. Therefore, the performance measures necessary for the evaluation of effective gauge face lubrication practice have not been developed. Currently, there are no specific performance measures available for heavy haul rail curve lubrication. Also, the performance of in-rail lubrication seems to be poor in most cases. Appropriate performance measures should be implemented that can accurately demonstrate the actual performance of the lubrication. This paper is focused on the development of effective performance measures based on lubrication theory, maintenance regime, field testings of different wayside lubrication equipment technology and different greases currently used on heavy haul lines. Extensive field tests have been conducted on the Queensland Rail Network’s North Coast Line, which is a dedicated coal line. Data were collected and analysed for the development of performance measures and cost-effective lubrication decisions. The presented performance measures and illustrative examples could be used by other types of railway networks for enhancement of rail/wheel asset life, asset availability, reliability and safety along with reduction of costs.
  PubDate: 2014-06-06T00:09:11-07:00
  DOI: 10.1177/0954409713482678|hwp:master-id:sppif;0954409713482678
  Issue No: Vol. 228, No. 5 (2014)
Evaluation of track geometry maintenance for a heavy haul railroad in
Sweden: A case study
- Authors: khouy, I. A; Schunnesson, H, Juntti, U, Nissen, A, Larsson-Kraik, P.-O.
  Pages: 496 - 503
  Abstract: The measurement and improvement of track quality are key issues in determining both the restoration time and cost of railway maintenance. Applying the optimal tamping strategy helps reduce maintenance costs, making operations more cost-effective and leading to increased safety and passenger comfort. In this paper, track geometry data from the iron ore line (Malmbanan) in northern Sweden, which handles both passenger and freight trains, are used to evaluate track geometry maintenance in a cold climate. The paper describes Trafikverket’s (Swedish Transport Administration) tamping strategy and evaluates its effectiveness in measuring, reporting and improving track quality. Finally, it evaluates the performance of the maintenance contractor and discusses the importance of the functional requirements stated in the outsourcing contracts.
  PubDate: 2014-06-06T00:09:11-07:00
  DOI: 10.1177/0954409713482239|hwp:master-id:sppif;0954409713482239
  Issue No: Vol. 228, No. 5 (2014)
Power harvesting systems design for railroad safety
- Authors: Pourghodrat, A; Nelson, C. A, Hansen, S. E, Kamarajugadda, V, Platt, S. R.
  Pages: 504 - 521
  Abstract: Railroad crossings represent a significant danger in railroad transportation systems. Each year thousands of accidents occur that involve trains and other vehicles at unprotected railroad crossings, resulting in hundreds of fatalities and injuries. Additionally, derailments occur on average once every 6 h across the United States due to mechanical failures and improperly maintained track, endangering property and lives. The lack of electrical infrastructure in remote areas is a primary barrier impeding the installation of safety enhancements such as warning light systems and track health monitoring sensors that could reduce the frequency of such accidents. Providing on-demand power by harvesting energy from deflecting railroad track during the passage of trains is a promising approach compared with the cost of installing electrical power lines or the lack of robust solar and/or wind power solutions. This paper discusses the design and development of several power harvesting devices capable of scavenging power from the vertical deflection of railroad track. The design of a cam-based generator device driven by the train wheels is also discussed. Simulation and testing results on these devices are also presented in this paper.
  PubDate: 2014-06-06T00:09:11-07:00
  DOI: 10.1177/0954409713482659|hwp:master-id:sppif;0954409713482659
  Issue No: Vol. 228, No. 5 (2014)
Influence of system parameters on the stability limit of the undisturbed
motion of a motor bogie
- Authors: Huang, C; Zeng, J, Liang, S.
  Pages: 522 - 534
  Abstract: In this article, the stability limit of the undisturbed motion of a simple railway motor bogie whose traction motors are fully suspended on the bogie frame is analysed. Under appropriate assumptions, equations of motion for the vehicle system are deduced by considering the lateral and yaw motions of the bogie frame, wheelsets and traction motors. Using root locus analysis, eigenvalues and eigenvectors of the equations are calculated, and a stability assessment for determining the bifurcation point is proposed. The vehicle speed at the bifurcation point is defined as the bifurcation speed where the equilibrium position of the vehicle system loses stability. Parametric studies are undertaken in order to investigate the respective effects of the traction motor's parameters on the stability of the vehicle system. It is found that the stiffness, damping and mass properties of the traction motor have significant influences on the bifurcation speed. There exists an optimum natural frequency for the motor suspension, below which a relatively high bifurcation speed is obtained. Finally, the effect of the bogie's parameters on the optimum natural frequency is investigated, and it is shown that the optimum natural frequency is significantly affected by the primary and secondary suspensions, and the wheel/rail contact conditions.
  PubDate: 2014-06-06T00:09:11-07:00
  DOI: 10.1177/0954409713488099|hwp:master-id:sppif;0954409713488099
  Issue No: Vol. 228, No. 5 (2014)
Large eddy simulation of the flow around a train passing a stationary
freight wagon
- Authors: Liu, Y; Hemida, H, Liu, Z.
  Pages: 535 - 545
  Abstract: In this paper, the effect of track spacing on the aerodynamic performance of a stationary double-stacked freight wagon passed by a high-speed passenger train is investigated using large eddy simulation (LES). The passenger train is a 1/20th scale model of an ICE2-shaped high-speed train and consists of nose, two coaches, inter-carriage gap and tail. Based on the speed and height of the passenger train, a flow Reynolds number of 2 x 105 is used in the simulation studies. To isolate the effect of the mesh resolution computations are performed using three different meshes: coarse, medium and fine, consisting of 3.2 x 106, 6.9 x 106 and 9.0 x 106 nodes, respectively. The results are also validated with available experimental data and a good agreement is demonstrated. The aerodynamic loads on the freight containers and passenger train are obtained during a passing process. High side force values are generated on the freight containers when the passenger train approaches followed by a sudden reduction when the nose of the passenger train passes the freight wagons. There is also a reduction in the side force when the tail of the passenger train passes the freight wagon followed by a significant increase when the wake flow hits the freight wagon. Similar behavior is observed for the lift and drag coefficients. The effect of track spacing is investigated by performing simulations at three different track spacing values: 3.5, 4 and 4.5 m. The results show that a reduction in track spacing generally increases the aerodynamic forces on both the freight wagon and passenger train.
  PubDate: 2014-06-06T00:09:11-07:00
  DOI: 10.1177/0954409713488096|hwp:master-id:sppif;0954409713488096
  Issue No: Vol. 228, No. 5 (2014)
Optimisation of track geometry inspection interval
- Authors: khouy, I. A; Larsson-Kraik, P.-O, Nissen, A, Juntti, U, Schunnesson, H.
  Pages: 546 - 556
  Abstract: The measurement and improvement of track quality are key issues in determining the time at which railway maintenance must be performed and its cost. Efficient track maintenance ensures optimum allocation of limited maintenance resources which has an enormous effect on maintenance efficiency. Applying an appropriate tamping strategy helps reduce maintenance costs, making operations more cost-effective and leading to increased safety and passenger comfort levels. This paper discusses optimisation of the track geometry inspection interval with a view to minimising the total ballast maintenance costs per unit traffic load. The proposed model considers inspection time, the maintenance-planning horizon time after inspection and takes into account the costs associated with inspection, tamping and risk of accidents due to poor track quality. It draws on track geometry data from the iron ore line (Malmbanan) in northern Sweden, used by both passenger and freight trains, to find the probability distribution of geometry faults.
  PubDate: 2014-06-06T00:09:11-07:00
  DOI: 10.1177/0954409713484711|hwp:master-id:sppif;0954409713484711
  Issue No: Vol. 228, No. 5 (2014)
Overview of issues and research related to special trackwork for shared
high-speed-rail passenger and heavy-axle-load freight operations
- Authors: Rapp, C. T; Kernes, R. G, Saat, M. R.
  Pages: 557 - 565
  Abstract: Special trackwork, including turnouts and crossing diamonds and their components, plays a vital role in railway infrastructure by providing route flexibility to trains as they travel across a network. As the interest in shared rail corridors involving heavy-axle-load freight traffic and high-speed-rail passenger traffic grows, special trackwork represents a significant challenge due to diverging loading characteristics and design priorities. This paper presents an overview of the issues related with special trackwork for shared rail corridors, as well as an in-depth analysis of the relevant research to date. The relevance of different shared operation types and research needs are also presented. This study can be used to assist in the planning of new passenger services on freight rail lines, or vice versa, in the USA, and may also be relevant to shared rail corridor development in other countries.
  PubDate: 2014-06-06T00:09:11-07:00
  DOI: 10.1177/0954409713486260|hwp:master-id:sppif;0954409713486260
  Issue No: Vol. 228, No. 5 (2014)