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Published By Czech Technical University In Prague - Central Library

2336-5382

2021 ◽  
Vol 31 ◽  
pp. 36-40
Author(s):  
Pavel Purkart ◽  
David Vodák ◽  
Tomáš Javořík ◽  
Martin Jacura

The aim of this article is to deal with the issue of high-speed railway lines (HSL) in the Czech Republic in response to the Fast connections conception ("Rychlá spojení" in Czech, abbreviation "RS"). Currently the RS1, RS2 and RS4 projects are the most watched during the preparation of the HSL network construction. The authors would like to focus on this issue from the wider point of view and to assess possible impact on the current lines of long-distance trains, the location of graphical timetable nodes and the way of the transport service on the area of the state.


2021 ◽  
Vol 31 ◽  
pp. 10-17
Author(s):  
Vojtěch Dybala

The importance of the railway transport of both goods and passengers continuously grows as it is in many points of view more ecological and economical solution in comparison with road transport. Just the importance has been supporting efforts to design more powerful and faster trains reaching traction powers more than 1.6 MW per a wheel-set or service top speed much more than 300 km/h till these days. To reach design which has enabled such a kind of performances it was necessary to research dynamic behaviour of railway vehicles. Both via laboratory measurements and simulations. The laboratory experiments have been carried out on a specially designed laboratory equipment called roller rigs. A laboratory equipped by roller rig for testing of the railway vehicle dynamic behaviour has been built at the Faculty of Mechanical Engineering at CTU in Prague, also within PhD studyprograms and SGS grants. Another powerful tool within research activities is a simulation. Kind of a such simulation will be presented by this contribution with the focus on the torsion dynamics of high-power fully-suspended drive of a railway vehicle, which has been developed also by PhD students under financial support of The Faculty of Mechanical Engineering and related grants.


2021 ◽  
Vol 31 ◽  
pp. 30-35
Author(s):  
Petr Nachtigall ◽  
Erik Tischer

This paper explores the minimum length of continuous sections of the high-speed line. The minimum length is examined in terms of the maximum speed of high-speed vehicles. Both traditional trainsets consisting of traction units and coaches, and train units were selected for examination. The graphs present the difference in the ability of the different vehicles to reach and use the maximumspeed.


2021 ◽  
Vol 31 ◽  
pp. 53-57
Author(s):  
Lukáš Týfa ◽  
Jan Kruntorád ◽  
Ondřej Tomaschko

The construction of the track is solved as a conventional (with track ballast) or as a ballastless track (without track ballast). When deciding on the choice of the most suitable track design for high-speed rail, it is necessary to emphasize that with increasing line speed, the requirements for the quality of the track geometry increase, including the size of the deviations of individual geometric parameters of the track from the projected values. When assessing the choice of track structure – especially for high-speed rails – it is therefore necessary and correct to assess the total costs (investment and operational) for a sufficiently long time. DB Netz AG’s present experience with a ballastless track since its first implementation in 1972 in Rheda station, for almost 50 years, shows that the required lifetime of 60 years has its real justification. In addition, current research and development in the field of ballastless track is moving towards extending the life of ballastless track well beyond this limit. The paper is focused on the comparison a ballasted and ballastless track construction. It deals in more detail with evaluation of the advantages and disadvantages of a ballastless track construction. The main objective is to assess the use of ballastless track structure for the construction of high-speed lines.


2021 ◽  
Vol 31 ◽  
pp. 5-9
Author(s):  
Michal Drábek ◽  
Dominik Mazel ◽  
Jiří Pospíšil

This paper compares chosen European high-speed railway (HS) networks in terms of their offer of HS passenger service. The criteria chosen for comparison are network topology, degree of service periodicity and degree of coordination between subsequent services. Only services with HS trains are taken into account. As a result, each examined network is classified according to prevailing approach to passenger service – either Line/Service (LS) Approach, where transfer connections are in general not anticipated, or Network (N) approach, with regular (mostly periodic) public transport lines and periodic transfer connections between them.The comparative analysis has shown that geography had crucial impact not only on national (or regional) HS line network, but on the HS operational concept as well.On trunk HS lines, which connect most populated agglomerations in particular country, there is always – at least during peak times – some form of periodic service, despite compulsory seat reservation (except state-owned carriers in Austria and Germany).Half of analyzed networks can be characterized by N approach – at least on trunk HS lines or within central "core" part of HS network.For Czech HS network, authors recommend to define a core network with application of Integrated Periodic Timetable.


2021 ◽  
Vol 31 ◽  
pp. 41-44
Author(s):  
Pavel Purkart ◽  
Jan Kruntorád ◽  
Lukáš Týfa

The aim of the paper is to set priority of The Fast Connection sections ("Rychlá spojení" in Czech, abbreviation "RS") building mentioned above by using the STEM method. The method is used to select projects with the maximum benefit if the budget is limited. There has not been set a limit for individual RS sections as a limitation of financial costs. The decisive factor is the order in which individual RS sections should be built on the basis of evaluation criteria.


2021 ◽  
Vol 31 ◽  
pp. 18-26
Author(s):  
Adam Hlubuček

This paper aims to summarize possibilities how to create data models of high-speed railway turnouts. The turnouts designed for high-speed operation require specific geometric solution. As the UIC RailTopoModel is considered an international recommendation in the field of data modeling of railway infrastructure, this issue is assessed in terms of models based on its principles. Solving this problem can affect the future development of the Multipurpose Railway Infrastructure Model gradually emerging at the CTU Railway Laboratory in Prague using the RailTopoModel principles.Whereas the RailTopoModel itself does not define any specific types of entities, the railML® 3.1 specifications are also used for assessment purposes. Turnouts are viewed both in terms of topology and in terms of functional infrastructure. In the final sections, recommendations are given on how to deal with the problems found, e. g. in terms of implementation into the Multipurpose Railway Infrastructure Model.


2021 ◽  
Vol 31 ◽  
pp. 1-4
Author(s):  
Jan Antoš

Aim of this article is to introduce and present advantages and possibilities of using simulation tools to calculate energy flows of tractive vehicle in all phases of its ride. The focus is on the braking phase, especially on the braking energy recuperation that offers the highest energy saving potential.Energetic simulation was carried out as a part of a current railway reconstruction study, which is a good example of possible energetic calculation use. Energetic calculation in the simulation are performed using so called "exact method" developed at the Faculty of Transportation. The advantage of the method is that it provides a high degree of accuracy. Due to the simulation calculation being performed in real-time, the user can enter the calculation even during the simulation. Crucial part ofevery simulation are quality input data, such as vehicle braking characteristic (including all working points below the envelope line together with the efficiency characteristics of the power train parts (engine, transmission, convertor and others)). Also, sufficiently precise (with a precision of 1 meter) railway track details (detailed geometrical and other information on the current and reconstructed railway track or on the railway track proposal.To present savings during the ride, the railway track section on the track Montreál-Sherbrooke was chosen. On this track, (especially electrification and partial reconstruction of the superstructure) is planned. Reconstruction level will be dependant on the local economical and social conditions. However, in the most optimistic case, total electrification of the track will be undertaken, or lower level of the reconstruction when the vehicles that have very similar characteristics. The railway track section is located between the cities of Montreál and Sherbrooke, that are 160 km apart. To compare the current, and possible future, state, comparison of energy consumption of the vehicle was conducted on the same track with the same geometrical characteristics.We can assume that the overall energy intensity of the ride on the newly reconstructed track (eg. with greater radius of the arches) will be lower than the overall energy intensity of the ride on the track before reconstruction. Current data on energetic consumption are not available, therefore they were obtained by simulation and verified by calculations and considered sufficiently accurate.Presumably, the input simulation parameters required for the simulation will not always be delivered in the sufficient quality or will be partly missing completely. In these cases they will be substituted by various algorithms, that can be machine-processed and that are part of the simulation calculations. One of the crucial algorithms is so called "moment efficiency". Its machine processingis not entirely developed and therefore, this simulation will be conducted without its usage. For financial reasons, simulation calculation was verified only by the theoretical physical calculation method. Based on several partial results, emergent computing tool is functional and sufficiently accurate. The simulation program is supposed to be experimentally verified after its finishing.The outcomes presented in this article are calculated by simulated computation and were not confronted with the real situation in any way. However, relevant calculation algorithms, processes and theoretical background of the simulation were already verified on the older software versions. Therefore, the simulated outcomes are supposed to be at least sufficiently accurate to provide preliminary study for the railway reconstruction. Presented calculations were executed by using author’s simulation software.Part of the methodology was taken from the previous, already verified, versions of the software for vehicle ride simulation.


2021 ◽  
Vol 31 ◽  
pp. 58-60
Author(s):  
Jan Vogl ◽  
Mária Jánešová

The development of foreign trade plays an important role in the Czech economy. The important foreign trade commodity item is Machinery and transport equipment (SITC 7). Railway vehicles is a part of this category, other means of transport (SITC 79).In order to maintain competitiveness and economic growth, it is necessary for the railway industry to intensify the innovation and the introducing of new technologies into production. One of the available options is a wider implementation of life cycle cost analysis, which enables to activate innovative efforts, as well as to improve technical and performance data.


2021 ◽  
Vol 31 ◽  
pp. 45-52
Author(s):  
Jiří Šlapák ◽  
Tomáš Michálek

This paper deals with the issue of dynamic effects of a high-speed railway vehicle on the track. Some aspects of vehicle/track interaction at higher speeds are described. In this context, a multi-body model of high-speed railway vehicle was created and several simulation scenarios were performed with this model. Furthermore, the simulations were evaluated with a focus on selected characteristics of the vehicle/track interaction.


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