Добірка наукової літератури з теми "Freight cars Dynamics"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Freight cars Dynamics".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Статті в журналах з теми "Freight cars Dynamics"
1
Fomin, O. V., and A. O. Lovska. "Research of the Vertical Dynamics of the Supporting Structures of Freight Cars Made of Round Pipes." Science and Transport Progress. Bulletin of Dnipropetrovsk National University of Railway Transport, no. 1(91) (February 15, 2021): 104–14. http://dx.doi.org/10.15802/stp2021/227223.
Повний текст джерелаАнотація:
Purpose. This study is aimed at determining the vertical dynamics of supporting structures of freight cars made of round pipes. Methodology. Mathematical modeling of the dynamic loading of the supporting structures of the main types of freight cars made of round pipes (gondola car, covered car, flat car, hopper car) was carried out. The studies were carried out in a plane coordinate system – the XZ plane. At the same time, it was taken into account that the car is moving in an elastic-viscous track so that the reactions of the track are proportional to both its deformation and the rate of this deformation. The studies were carried out for the case of empty cars. The joint inequality is described by a periodic function. The calculation was performed at a speed of 80 km/h. Differential equations of motion were solved in the MathCad software package using the Runge-Kutta method. Findings. Based on the mathematical modeling of the dynamic loading of the supporting structures of cars made of round pipes, the main indicators of their dynamics were obtained: accelerations acting on the supporting structures in the mass center, forces acting in the spring suspension of bogies, dynamics coefficients. For gondola car, covered car, and hopper car, the acceleration at the mass center of the supporting structure is within 0.4 g, and for a flat car – 0.5 g. It was found that the obtained indicators of the dynamics of cars made of round pipes are within the permissible limits. The accelerations acting on the supporting structures of cars made of round pipes are almost the same as those obtained for prototype cars. At the same time, the motion of cars is assessed as "excellent" for gondola car, covered car, and hopper car and "good" for flat car. Originality. Mathematical modeling of the dynamic loading of the supporting structures of cars from round pipes was carried out and the main indicators of their dynamics were obtained. Practical value. The research carried out will contribute to the creation of recommendations for the design of supporting structures of freight cars of round pipes, and can also be useful developments in the creation of innovative car designs.
2
Маслак and A. Maslak. "PRINCIPLES OF ESTIMATION OF OPERATIONAL PARAMETERS OF FREIGHT STATION FUNCTIONING IN TERMS OF TRANSPORT PROCESS DYNAMICS." Alternative energy sources in the transport-technological complex: problems and prospects of rational use of 2, no. 2 (December 17, 2015): 790–96. http://dx.doi.org/10.12737/19565.
Повний текст джерелаАнотація:
At present time freight stations operation is complicated by raised dynamics of production and transport processes. Under the given handling capacity, this circumstance affects duration of processing of inbound and internal flow of freight cars. New approaches to analysis, assessment of operational characteristics, and designing of freight railway stations within industrial enterprises, considering dynamics of production and transport environment, are developed.
3
Shvets, A. O. "INFLUENCE OF LATERAL DISPLACEMENT OF BOGIES ON THE FREIGHT CAR DYNAMICS." Science and Transport Progress. Bulletin of Dnipropetrovsk National University of Railway Transport, no. 6(90) (April 8, 2021): 66–81. http://dx.doi.org/10.15802/stp2020/223519.
Повний текст джерелаАнотація:
Purpose. The work is aimed at determining the influence of the lateral displacement of a freight car bogie, taking into account the value of the movement speed on its main dynamic indicators and interaction indicators of the rolling stock and the track. Methodology. The quantitative assessment of dynamic indicators was obtained by the method of mathematical and computer modeling. The design scheme of the car takes into account the interaction peculiarities of cars as part of the train: the possibility of all modes of body vibration in space, the transmission of longitudinal force from neighboring cars in vertical and horizontal directions, taking into account the technical condition of individual parts of the car and their design features, as well as various operating conditions. Findings. During the research, a mathematical model of a coupling of five freight cars was applied to study the dynamic loading of a gondola car and a track. Main dynamic and interaction indicators of the rolling stock and the track in case of transverse bogie displacement when moving along curved track sections assessment were assessed. The maximum possible values of the lateral displacement of the freight car bogie were substantiated. Originality. The mathematical model of the coupling of freight cars in the train has been improved. In the calculation schemes describing the vibrations of the cars, the peculiarities of the freight car bogies, lozenging of the bogie side frames are taken into account. The model makes it possible to study the effect of changing rotation angle of the central axis of the car body, which in turn leads to the lateral displacement of bogies relative to each other, on the main dynamic and interaction indicators of the rolling stock and the track. For the first time, the influence of transverse displacement of the bogie was investigated, taking into account the wear of its parts and assemblies when moving on track sections with unevenness. Practical value. The calculation results can be used to assess the influence of the bogie transverse displacement on the dynamic qualities of the rolling stock and interaction indicators of the rolling stock and the track, taking into account the wear of parts and units of the bogie when moving in straight and curved track sections with irregularities. The application of the results obtained will contribute to an increase in the stability of freight rolling stock in the conditions of increasing travel speeds, which in turn will allow developing technical conditions for the implementation of resource-saving technologies for transporting goods that meet the safety requirements of train traffic.
4
Shevchenko, D. V., M. A. Kudryavtsev, A. M. Orlova, S. A. Ponomarev, A. M. Sokolov, and Yu V. Savushkina. "Numerical modeling of the dynamics of the clutch couplers." Vestnik of the Railway Research Institute 78, no. 3 (July 28, 2019): 155–61. http://dx.doi.org/10.21780/2223-9731-2019-78-3-155-161.
Повний текст джерелаАнотація:
One of the priorities of the program “Strategy for the development of railway transport in the Russian Federation until 2030” is the introduction and development of heavy haul traffic, allowing to ensure the increasing volume of freight traffic and significantly improve the efficiency of railways. Main challenges for scientific research and design development to ensure the creation of freight cars for heavy haul traffic, along with an increase in longterm load and decrease in tare weight, include the issue of increasing the load from the wheelset to the rails to 27 tons for heavy haul cars SA-3T and couplers SA-3. It is shown that increasing the load from the wheelset to the rails up to 27 tons while maintaining the dynamic running load within the normalized values can be achieved by increasing calculated deflection of the spring suspension of the truck, which in turn leads to an increase in the possible height difference between the couplings of adjacent cars. Authors explain necessity of putting into operation a coupler for heavy haul cars SA-3T, providing an increase in the vertical coupler contour line up to 210 mm. Regulatory documents governing the provisions of automatic coupling devices in freight cars were analyzed. Dynamic computational models have been developed that describe the behavior of automatic couplings in the process of coupling cars, taking into account the inertial characteristics of all parts included in the assembly, the geometric nonlinearity associated with their contact interaction, and the elastic-damping properties of the absorbing device. Verification of calculated dynamic model has been carried out. Numerical experiments simulating the coupling of the considered automatic coupling devices with the most unfavorable possible combinations of horizontal deviations and rotation angles were performed. It is confirmed that the developed design of the coupler CA-3T provides grip when there is a possible difference between the lower surfaces of the locks of adjacent coupler up to 210 mm both between themselves and with the typical coupler CA-3.
5
Ushkalov, V. F., and N. V. Bezrukavyi. "Study of the dynamics of freight cars with radial-type trucks." Technical mechanics 2020, no. 1 (February 27, 2020): 106–13. http://dx.doi.org/10.15407/itm2020.01.106.
Повний текст джерела
6
Sverdlov, Vadim Borisovich, and Vasiliy Fedorovich Lapshin. "Car fleet safety assurance on non-public railway tracks." Transport of the Urals, no. 4 (2021): 33–39. http://dx.doi.org/10.20291/1815-9400-2021-4-33-39.
Повний текст джерелаАнотація:
The paper considers problems connected with car fleet safety assurance, it highlights aspects that require a scientific solution. Special attention is paid to assessment of influence of railway transport structural reform on dynamics of damage growth of freight cars. The paper shows that the greatest amount of damage occurs during freight and shunting operation on non-public railway tracks while a technological level of organization and execution of freight operations on industrial enterprises can’t guarantee an exception of car damage risks. On the example of open-box cars unloading with the use of overhead vibration machines the authors have considered aspects of safety assurance that require a scientific justification. They have highlighted priority tasks that it is necessary to solve: revision of normative and technical documentation on freight car safety assurance, arrangement of interaction between car owners, a railway infrastructure owner and owners of non-public railway tracks, development of methodological basics for organization of car fleet safety assurance system.
7
Matyash, Yu I., and I. A. Gadzhiev. "Development of an onboard monitoring device for freight car shock-absorbing device’s technical condition." Vestnik of the Railway Research Institute 78, no. 4 (November 25, 2019): 218–26. http://dx.doi.org/10.21780/2223-9731-2019-78-4-218-226.
Повний текст джерелаАнотація:
Good technical condition of rolling stock is an important consideration for increasing safety in train traffi c. Safety is the state’s priority in the development and modernization of the railroad industry. The goal of this study is to develop an onboard monitoring device for a freight car’s shock-absorbing device’s technical condition. This justifi es the need to control the serviceability of the unit and the urgency to equip freight cars with onboard monitoring systems. The following tasks were set and resolved: collection and analysis of information on the dynamics of changes in the number of faults of freight cars serviced at the sites of the current uncoupling repair of Russian companies from 2008 to 2018; study the expediency of the primary control of serviceability of different units of the freight car; collection and analysis of information including statistical data, scientifi c publications, and thesis on the effect of a failed shock-absorbing device on other units of the freight car and reduction of the train’s overall traffi c safety. The study enabled development and manufacturing of a mockup onboard monitoring device freight car shock-absorbing device’s technical condition, with its functional capabilities described. To increase the diagnostics accuracy, technology defi ning failure criteria of the controlled unit and reduction of its operation effectiveness is developed. The main recommendations for using the proposed onboard device are also provided. The principal advantages of the device are underlined and reasons for freight rolling stock owners to equip their cars with the developed system are advanced.
8
Shvets, A. O. "INTERACTION DYNAMICS OF SOME TYPES OF FREIGHT CARS WITH A RAILWAY TRACK." Science and Transport Progress. Bulletin of Dnipropetrovsk National University of Railway Transport, no. 5(89) (December 2, 2020): 142–59. http://dx.doi.org/10.15802/stp2020/217649.
Повний текст джерела
9
Egorov, Yuriy Vladimirovich, Liliya Faatovna Kazanskaya, and Nadezhda Vyacheslavovna Saks. "Influence of development of market of freight cars operation upon operation efficiency indexes of railway transport." Transportation systems and technology 3, no. 3 (September 15, 2017): 162–75. http://dx.doi.org/10.17816/transsyst201733162-175.
Повний текст джерелаАнотація:
Purpose. The article is devoted to estimation of influence of process of development of market of freight cars operation upon operation efficiency indexes of Russia’s railway transport. The existing qualified viewpoints on this issue have been considered. Methodology. For quantitative evaluation, the authors have used comparative analysis methods and econometric modeling based on JSC “RZD” and Federal State Statistics Service data of the period from 2003 till 2016. Results. According to the results of econometric modeling, it has been found out that statistically important influence of development of freight cars operation market upon indexes of operation efficiency of Russia’s railway transport is present only in one part of variable - “amount of deliveries, performed within normative (stipulated) period”. At the same time, indexes of operation efficiency of Russia’s railway transport demonstrate negative dynamics only from 2003 till 2009-12; from then on, most of these indexes have been showing sustainable positive tendency, having recovered from initial negative shock. This kind of shock might be a reaction to change of level of market development of freight cars operation in Russia, but this does not apply to all indexes of operation efficiency of JSC “RZD”.
10
Han, Hui Shi, Mei Han, and Xiao Xia Wang. "Study on Lateral Vibration Offsets of Speed Increased Freight Cars on the Tangent Track." Advanced Materials Research 779-780 (September 2013): 567–71. http://dx.doi.org/10.4028/www.scientific.net/amr.779-780.567.
Повний текст джерелаАнотація:
According to the vehicle dynamics theory, the dynamics simulation models of single-vehicle NX70H flat marked loading capacity of 70t with K5 bogies and NX70 flat marked loading capacity of 70t with K6 bogies under certain loading and running conditions were established by SIMPACK, in order to discuss the change rules of the roll angles, the yaw angles, the lateral offsets and the maximum lateral vibration offsets. Based on the statistical analysis of data calculated by SIMPACK, the results of dynamics single-vehicle models of the two wagon types running on Chinese I and III grade railway lines respectively were compared. Simulation results show that the running speed, the line condition and the height distancing the rail surface all have a significant impact on the maximum lateral vibration offset.
Дисертації з теми "Freight cars Dynamics"
1
Shestakova, Anzhela. "Development of mathematical models for freight cars subject to dynamic loading." Thesis, Keele University, 2015. http://eprints.keele.ac.uk/2343/.
Повний текст джерелаАнотація:
This research is inspired by mathematical modelling of railcar dynamics and deals with developing a methodology for estimating the impact loads acting on freight cars using measured acceleration data in order to determine their limiting magnitudes for the alarm generation. The developed scheme consists of the following steps. First, artificial neural network technology (ANN) is adapted to predict longitudinal forces in freight cars. Impact tests data for accelerations and forces were used for training ANN. The issue related to the lack of experimental results for training the network is addressed. A possibility of alternative theoretical training using mathematical models is studied. A restricted scope of conventional mathematical models based on rigid body dynamics is discovered. In particular, these models ignore the effect of self-equilibrated loads and internal dissipation. Next, an advanced perturbation model is derived, taking into account low frequency internal motion with inhomogeneous stiffness, density, and viscosity incorporated. The developed advanced model is applied to the evaluation of impact forces arising at coupled impact. The aforementioned model follows from a low-frequency analysis of a viscoelastic inhomogeneous bar, subject to end loads. The longitudinal variation of the problem 2 parameters is taken into consideration. Explicit asymptotic corrections to the conventional equations of rigid body motion are derived in an integro-differential form. The refined equations incorporate the effect of an internal viscoelastic microstructure on the overall dynamic response. Comparison with the exact time-harmonic solutions for extension and bending of a bar demonstrates the efficiency of the developed approach.
2
Berghuvud, Ansel. "Curving performance and nonlinear dynamic behaviour of freight cars with three-piece bogies /." Luleå, 2001. http://epubl.luth.se/1402-1544/2001/09/index.html.
Повний текст джерела
3
Мельничук, Василь Олексійович, Василий Алексеевич Мельничук та Vasily O. Melnichuk. "Підвищення безпечної швидкості вантажних вагонів шляхом оснащення стабілізаційними пристроями". Thesis, Видавництво Дніпропетровського національного університету залізничного транспорту імені академіка В.Лазаряна, 2011. http://eadnurt.diit.edu.ua/jspui/handle/123456789/812.
Повний текст джерелаАнотація:
Мельничук, В. О. Підвищення безпечної швидкості вантажних вагонів шляхом оснащення пристроями стабілізації руху: авт. дис. к. т. н.: 05.22.07 / В. О. Мельничук; Дніпропетр. нац. ун-т залізн. трансп. ім. акад. В. Лазаряна. - Д., 2011.UA: АНОТАЦІЯ. Дисертація присвячена забезпеченню стійкості руху вантажних вагонів колії 1520 мм із швидкістю 120 км/год (100 км/год – для старотипних) на протязі усього їх життєвого циклу (за умови якісного технічного утримання та ремонту). Показано, що існуючі обмеження швидкості поїзної та маневрової роботи до 70÷80 км/год пов’язані з величиною критичної швидкості вагонів на візках мод. 18-100 (з клиновими «гасниками Ханіна»), перевищення якої складає загрожує безпеці руху і, як правило, закінчується аварійними сходами з рейок. Визначені ознаки втрати стійкості руху вантажними вагонами, залежність критичної швидкості від зносів ходових частин, стану завантаженості вагона та плану колії. Показано, що демпфуванню виляння частин візків мод. 18-100 перешкоджають «зайвий» конструктивний ступінь вільності та некомпенсовані зноси клинового гасника. Вплив вказаних факторів вдалось усунути під час модернізації вагонів за проектом С.03.04 (з елементами »А. СТАКІ» — інструкція ЦВ-0083). Проведено аналіз безпечності реалізації конструктивної швидкості вагонами нового покоління на візках мод.18-7020, 18-579 та ін. Розроблено альтернативний спосіб збільшення критичної швидкості вагонів існуючого парку шляхом їх ремонту за технологією «ДНІПРО» для можливості їх подальшої безпечної експлуатації з швидкістю до 100 км/год (категорія «s» за класифікацією ОСЗ/МСЗ/UIC).
RU: АННОТАЦИЯ. Диссертация посвящена обеспечению устойчивости движения грузовых вагонов колеи 1520 мм со скоростью 120 км/ч (100 км/ч – для старотипных) во всей продолжительности их жизненного цикла (при условии качественного технического содержания и ремонта). Показано, что существующие ограничения скорости поездной и маневровой работы до 70÷80 км/ч связаны с величиной критической скорости вагонов на тележках мод. 18-100 (с клиновыми «гасителями Ханина»), превышение которой составляет угрозу безопасности движения и, как правило, заканчивается аварийными сходами с рельсов. Определены признаки потери устойчивости движения грузовыми вагонами, зависимость критической скорости от износов ходовых частей, состояния загруженности вагона и плана колеи. Показано, что демпфированию виляния частей тележек мод. 18-100 препятствуют «лишняя» конструктивная степень свободы и некомпенсированные износы клинового гасителя. Влияние указанных факторов удалось устранить при модернизации вагонов по проекту С.03.04 (с элементами «А. СТАКИ» - инструкция ЦВ УЗ-0083). Проведен анализ безопасности реализации конструктивной скорости вагонами нового поколения на тележках моделей 18-7020, 18-579 и др. Теоретическое исследование критической скорости грузового вагона выполнено двумя способами: с использованием теоремы А. М. Ляпунова (с заменой элементов фрикционного трения эквивалентными вязкими) и путем определения устойчивости на компьютерной динамической модели. Последний способ дал более достоверные результаты определения критических скоростей и параметров автоколебаний при потере устойчивости как типовым полувагоном, так и оборудованным стабилизирующими устройствами –упругими скользунами и штыревыми передачами. Разработана процедура обработки видеосъемки поперечных смещений колесной пары движущегося вагона в путевом зазоре с построением характеристики спектральной плотности, позволяющей достоверно определить наличие автоколебаний, как первичного признака потери вагоном устойчивости движения. Разработан и исследован альтернативный способ увеличения критической скорости вагонов существующего парка путем их деповского ремонта по технологии «ДНЕПР» с оборудованием специальными стабилизирующими устройствами – упругими скользунами ТАУС и штыревыми передачами. Расчеты на конечно-элементной 3D-модели, построенной из более 15 тыс. элементов, показали, что прочность и надежность боковины тележки после ремонта не снизились. Динамическими испытаниями подтверждено, что после такого ремонта возможна дальнейшая безопасная эксплуатация вагона со скоростью до 100 км/ч (категория «s» за классификацией ОСЖД/МСЖД/UIC). Расчет экономической эффективности от повышения скорости рудных поездов (6 составов ежесуточно) по направлению Кривой Рог –Ужгород (2,7 тыс. км) показал, что достигается сокращение используемых вагонов на 690 ед.,, локомотивов — на 11ед., годовая экономия составит 30 млн. руб. на 100 км. пути. Приказом Укрзализныци от 10.07.2007 г. № 365Ц утверждена инструкция о первом этапе повышения скорости грузовых поездов до 90-100 км/ч.
EN: SUMMARY. Dissertation is devoted providing of firmness of motion at a speed of 100÷120 km/h of freight carriages of track 1520 mm on all of duration them life cycle (subject to the condition high-quality technical maintenance and repair). It is retuned that existent limitations of speed of train and mobile work to 70÷80 km/h are related to the size of stalling speed of carriages on the light carts of fashion 18-100 (with «absorber wedge type Khanin»), exceeding of which makes a threat safety of motion and, as a rule, ends with an emergency stair from rails. The signs of loss of firmness of motion freight carriages are certain, dependence of stalling speed on wear surfaces of workings parts, to the state of work-load of carriage and plan of track. It is retimed that to damping of wagging of parts of light carts of fashion 18-100 «еxtra» hinder structural degree of freedom and wear out uncompensated wedge absorber. Influence of the indicated factors succeeded to be removed during modernization of carriages on the project S.03.04 (with elements »A. Staki» is instruction of ЦВ-0083). The analysis of unconcern of realization of strctural speed is conducted by the carriages of new generation on the light carts of fashions 18-7020, 18-579 and other. The alternative method of increase of stalling speed of carriages of existent park is developed by their repair on technology «DNEPR» for possibility them subsequent safe exploitation with speed to 100 km/h (a category of «s» is after classification of UIC).
Книги з теми "Freight cars Dynamics"
1
Fedorovich, Tat'yana, Natal'ya Kubrak, S. K. Tevs, and A. V. Dmitrenko. Organization and management of a private fleet of freight cars: an economic approach. ru: INFRA-M Academic Publishing LLC., 2022. http://dx.doi.org/10.12737/1860935.
Повний текст джерелаАнотація:
The monograph discusses theoretical and practical issues related to the completion of the implementation of the introduction of new forms of ownership in the formation of the railway holding JSC "Russian Railways". The organizational and economic results of the structural reform of railway transport in Russia are analyzed in comparison with the experience of modern reform of foreign railway transport. The variants of transformation of the modern cargo transportation management system in the new economic conditions are proposed.
The main results of the study of modern economic and organizational conditions of cargo transportation, taking into account the specifics of working with a private car fleet, are presented. Based on a large-scale analysis of the loading dynamics of the main directions of the Russian Railways network and the resulting unevenness of operational work, new approaches are proposed for the formation of the market of freight operators of rolling stock.
An economic assessment of the implementation of scenario options for the introduction of technological outsourcing is given on the example of JSC "Federal Freight Company" with the justification of a methodological approach for the formation of a consolidated fleet of wagons based
on the algorithm of the cost method for calculating the throughput during the consolidation of a fleet of freight wagons.
For practitioners and researchers involved in cargo transportation management, forecasting and formation of private fleets of freight cars. It will be useful for graduate students, undergraduates and students of economic faculties of railway universities when studying courses in the economics of railway transport and the cost of freight transportation.
2
International Congress of Theoretical and Applied Mechanics (20th 2000 Chicago, Ill.). ICTAM: Selected papers from the 20th International Congres [sic] of Theoretical and Applied Mechanics held in Chicago, 28 August-1 September 2000. Lisse, Netherlands: Swets & Zeitlinger, 2001.
Знайти повний текст джерелаЧастини книг з теми "Freight cars Dynamics"
1
Horn, H., A. Jaschinski, and S. Sedlmair. "Dynamic Simulation of Freight Cars with Nonlinear Suspension- and Buffer-Models During Curving." In The Dynamics of Vehicles on roads and on tracks, 161–68. London: CRC Press, 2021. http://dx.doi.org/10.1201/9781003210894-22.
Повний текст джерела
2
Gorbunov, Mykola, Serhii Kara, Olegas Lunys, and Gediminas Vaičiūnas. "Improving the Dynamics of Bogies of Railway Freight Cars by the Spring Suspension Enhancement." In TRANSBALTICA XI: Transportation Science and Technology, 220–24. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-38666-5_23.
Повний текст джерела
3
Orlova, Anna M., Ekaterina A. Rudakova, Denis V. Shevchenko, Artem V. Gusev, and Maxim A. Kudryavtsev. "Simulation and Experimental Assessment of the Dynamic Performance of Articulated Freight Cars." In Lecture Notes in Mechanical Engineering, 386–96. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-07305-2_39.
Повний текст джерелаТези доповідей конференцій з теми "Freight cars Dynamics"
1
Ansari, Masoud, Davood Younesian, and Ebrahim Esmailzadeh. "Effects of the Load Distribution Patterns on the Longitudinal Freight Train Dynamics." In ASME 2007 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/detc2007-35823.
Повний текст джерелаАнотація:
A comprehensive parametric study is carried out on the longitudinal dynamics of a freight train having different loading patterns. A nonlinear time domain model, with one locomotive and nine wagons, is considered. In another simulation the train model has two locomotives and eight wagons, and in both models, every two cars are connected to each other through an automatic coupler. The effects of different load distribution patterns on the coupler forces for the cases of ascending, descending, constant, ascending-descending and descending-ascending are investigated through a parametric sensitivity study. In order to investigate how an empty wagon and its position in a train-consist model may affect the overall longitudinal dynamic behavior of freight trains a second computer simulation model has been developed. Moreover, the best possible position for the second locomotive with the objective of reaching to the lower longitudinal forces, in the case that an additional locomotive is included will be discussed. Finally, an investigation is carried out to determine the kind of couplers with their relevant specifications that must be installed in different positions of a train-consist in order to improve the longitudinal train dynamic behavior.
2
Jacobsen, Karina, David Tyrell, and Patricia Llana. "Observed Equipment Damage and Analytically Estimated Car Decelerations in Selected Passenger Train Accidents." In 2012 Joint Rail Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/jrc2012-74118.
Повний текст джерелаАнотація:
The Federal Railroad Administration has conducted a number of detailed investigations of passenger train accidents which result in fatal injuries and/or multiple serious injuries. The objective of these investigations is to reconstruct the sequence of events and to determine the causal mechanisms for injuries and fatalities. This paper presents a reconstruction of the sequence of events and the train collision dynamics results for three accidents: - the passenger train to freight train collision with a closing speed of 80 mph in Chatsworth, California on September 12, 2008; - the passenger train to freight train collision with a closing speed of 33 mph in Chicago, Illinois on November 30, 2007; - the passenger train to freight car collision with a closing speed of 23 mph in Canton, Massachusetts on March 25, 2008. The reconstructions are developed from information gathered during field investigations of occupant injury (via interview and reports), damage to the interior fixtures, structural damage to the equipment, and wayside damage. Engineering analyses are then conducted to integrate the data gathered during the field investigation, including train collision dynamics modeling which estimates the gross motions of each of the rail cars during the collision. To assure that the model reasonably captures the collision dynamics, model results are first compared with the post-accident equipment damage information gathered in the investigations. The model is then used to estimate the severity of the decelerations experienced by the occupants. The Secondary Impact Velocity (SIV) provides an indication of severity of the interior environment experienced by the passengers and crew during the accident. In a companion paper, the SIVs are correlated with the observed level of damage to the interior seats and fixtures. The selected accidents represent a range of collision conditions, with closing speeds from 23 to 80 mph, single- and multi-level passenger cars, and colliding freight equipment from a long train to a single car. The selected accidents are similar in that in all cases the passenger trains are locomotive-led. The differences in collision speed and mass of the colliding equipment resulted in substantial differences in the observed damage to the equipment as well as differences in the estimated SIVs. These differences are discussed in the paper.
3
Vithani, Anand R., Graydon F. Booth, Anand Prabhakaran, Som P. Singh, David C. Brabb, Srinivas Chitti, Monique F. Stewart, and S. K. Punwani. "Freight Truck for Higher Speed Operations." In 2010 Joint Rail Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/jrc2010-36244.
Повний текст джерелаАнотація:
The current freight railroad operations are restricted to a maximum speed of 80 mph partly due to lateral instability of conventional freight trucks at higher speeds. The three-piece truck, a workhorse of the railroad industry for over 100 years, and its variations are susceptible to hunt at 50–55 mph when empty and 90–100 mph in loaded conditions. Design attempts to increase high-speed stability generally lead to diminished curving performance and increased risk of derailment. In this paper we describe a true pendulum suspension based freight truck that is designed to achieve stable operations up to 150 mph without compromising curving performance. The truck’s performance has been analyzed using an industry standard vehicle dynamics simulation tool. The AAR MSRP M-1001 Chapter 11 ‘Service-Worthiness Tests and Analyses For New Freight Cars’ were used to qualify the design where applicable. Traditional tread brakes are supplemented with axle-mounted disc brakes to provide safe braking capabilities beyond 110 mph. Two full-size 70-ton prototypes have been assembled using off-the-shelf and fabricated components. Yard tests have shown that the truck curves properly even under very tight curving conditions.
4
Ahmadian, Mehdi. "On the Application of Magneto-Rheological Fluid Technology for Improving Rail Vehicle Dynamics." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-33250.
Повний текст джерелаАнотація:
The primary purpose of this paper is to review the fundamentals, concepts, and merits of new technologies that hold a promise for helping the railroad industry in its missions. The author hopes that this paper will be the first of a series of papers that will be devoted to reviewing new technologies that are on the horizon and can benefit the rail industry, in a manner similar to the current papers that report on the progress of different aspects of transit and passenger cars, locomotives, and freight cars. The fundamental difference between this paper and current papers is that it will be devoted to new technologies that are in a more distant horizon (10–15 years), as opposed to the more immediate future developments that are covered in current papers. The first technology that will be highlighted is the magneto-rheological (MR) technology that has received a tremendous amount of attention in the past five years in the transportation industry, in particular for automotive applications. This paper will provide an overview of MR technology and its common applications, and provide some fruits for thoughts on how MR technology can be used in the rail industry.
5
Hazrati Ashtiani, Iman, Subhash Rakheja, A. K. W. Ahmed, and Jimin Zhang. "Hunting Analysis of a Partially-Filled Railway Tank Car." In 2015 Joint Rail Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/jrc2015-5631.
Повний текст джерелаАнотація:
General purpose railway tank cars similar to road tankers are known to transport liquid cargo in partial-fill state due to variations in liquid cargo density and governing axle load limits. It is widely reported that the cargo movements constitute additional forces and moments that could strongly affect the wheel-rail interactions and coupling forces, and thereby the directional dynamics of the wagon. In this study, the linear slosh theory is used to describe the liquid cargo movement in the roll plane by a simple pendulum, which is integrated into a comprehensive nonlinear multi-body model of a three-piece truck to study the effects of liquid cargo slosh on lateral dynamics of the tank car. The model also incorporates the nonlinear secondary suspension restoring and damping forces, attributed to friction of the wedges, using the non-smooth contact method in addition to the geometric constraints of various components. The wheel/rail contact forces are simulated considering non-elliptical wheel-rail contact using the FASTSIM algorithm. The lateral dynamic responses of the multi-body model of a freight car with partially filled liquid load and an equivalent rigid cargo are evaluated to study the effect of cargo movement on the critical speed and the wheelset hunting oscillations frequency. The results obtained considering different fill ratios of the liquid cargo suggest that the fluid slosh yields additional damping effect on the lateral dynamics of the car. Liquid cargo movement within partly-filled tank car could thus yield a beneficial influence on the wheelset hunting. This was evidenced from the phase relationship between the lateral oscillations of the pendulum and the bogie/wheelset. Consequently, a partially filled tanker resulted in relatively higher critical hunting velocity compared to that of the wagon with equivalent rigid cargo.
6
Gonzalez, Francisco, Anand Prabhakaran, Graydon F. Booth, Florentina M. Gantoi, and Arkaprabha Ghosh. "Validation of Methodology to Evaluate Risk Reduction in Tank Car Derailments." In ASME 2018 Verification and Validation Symposium. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/vvs2018-9331.
Повний текст джерелаАнотація:
Critical derailment incidents associated with crude oil and ethanol transport have led to a renewed focus on improving the performance of tank cars against the potential for puncture under derailment conditions. Proposed strategies for improving accident performance have included design changes to tank cars, as well as, operational considerations such as reduced speeds. In prior publications, the authors have described the development of a novel methodology for quantifying and characterizing the reductions in risk that result from changes to tank car designs or the tank car operating environment. The methodology considers key elements that are relevant to tank car derailment performance, including variations in derailment scenarios, chaotic derailment dynamics, nominal distributions of impact loads and impactor sizes, operating speed differences, and variations in tank car designs, and combines these elements into a consistent framework to estimate the relative merit of proposed mitigation strategies. The modeling approach involves detailed computer simulations of derailment events, for which typical validation techniques are difficult to apply. Freight train derailments are uncontrolled chain events, which are prohibitively expensive to stage and instrument; and their chaotic nature makes the unique outcome of each event extremely sensitive to its particular set of initial and bounding conditions. Furthermore, the purpose of the modeling was to estimate the global risk reduction expected in the U.S. from tank car derailments, not to predict the outcome of a specific derailment event. These challenges call into question which validation techniques are most appropriate, considering both the modeling intent as well the availability and fidelity of the data sets available for validation. This paper provides an overview of the verification and validation efforts that have been used to enhance confidence in this methodology.
7
Aboubakr, Ahmed K., and Ahmed A. Shabana. "Numerical Study on the Delay Effect of Air Brake Mass Flow on Train Coupler Forces." In 2020 Joint Rail Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/jrc2020-8013.
Повний текст джерелаАнотація:
Abstract In existing freight-train braking systems, braking is applied on individual cars sequentially at the speed of the air pressure. In the case of long trains that consist of hundreds of rail cars, there is a time delay that results in large and impulsive compressive and tensile coupler forces. These coupler forces compromise the train safe operation and stability, make train handling difficult, cause track damage, raise significantly the maintenance cost, and increase the stopping distances which can lead to serious accidents. The objective of this investigation is to investigate the effect of the brake-delay time on the train longitudinal dynamics (LTD) coupler forces by integrating for the first time detailed three-dimensional coupler and air-brake force models. A spatial non-linear coupler model that takes into account the geometric nonlinearities is employed in order to allow for capturing arbitrary three-dimensional rail-car motion and coupler kinematic degrees of freedom that cannot be captured using existing simpler models. This coupler model is integrated with a detailed air brake model that consists of the locomotive automatic brake valve, air brake pipe, and car control unit (CCU) in order to evaluate conventional air brake force models that account for the air-flow effect in long train pipes as well as the effect of leakage and branch pipe flows. The coupling between the air brake, locomotive automatic brake valve, car control units, and train equations is established and used in the nonlinear LTD simulations, which are performed using the computer software ATTIF (Analysis of Train/Track Interaction Forces). Different LTD braking scenarios are considered and the effect of brake signal time delay on the coupler forces is examined. The results obtained in this study demonstrate the importance of applying all brake forces simultaneously in order to ensure train stability and safety.
8
Dawson, Richard W., Darrell Iler, and Kevin Koch. "New AAR Procedure Permitting Freight Car Life Beyond 50 Years." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-82848.
Повний текст джерелаАнотація:
The Interchange Rules of the Association of American Railroads (AAR) limit the life of freight cars to 50 years from the date originally built. Recently, however, the AAR has instituted a new provision under Interchange Rule 88 that permits cars to operate for up to 65 years since their built date. The procedure incorporates two basic portions; demonstrating that the carbody has the structural integrity to last for a total life of 65 years and upgrading specific components on each car. After applying to the AAR Equipment Engineering Committee (EEC) requesting that ILS be granted to a particular group of cars, the car owner has two optional methods to demonstrate the structural integrity of the selected cars. The first option is to perform structural inspections on a specified number of representative cars and to perform a full-scale fatigue test on a test car. In place of the fatigue test, the second option is to perform structural inspections on a larger number of cars and conduct follow-up inspections every five years after receipt of approval. The physical fatigue test incorporates modern engineering best practices by utilizing finite element modeling and full-scale accelerated fatigue testing (AFT). Following the creation of a representative model, several load conditions, both real and worst-case, are then applied to determine the high-stress locations. Using instrumentation at the high-stress locations, a full-scale test is conducted with the car operating in a typical service environment. The objective of full-scale testing is to obtain real strain data and input loads produced by typical environment conditions. AFT enables the required load cycles to be applied to the test car in a dynamic test fixture in weeks or months versus years of actual service. A rapid accumulation of fatigue-damaging cycles representative of the remaining years necessary to bring the total life of the test car to 65 years are applied to the car. The requirements for the components to be replaced or upgraded under Rule 88 are similar to those for new cars and for rebuilt cars. Some components, such as air brake control valves, are to be upgraded to more recent standards. Others are to be replaced in kind with reconditioned parts. Even though the carbody is permitted to operate beyond 50 years, components must still comply with existing AAR and Federal Railroad Administration (FRA) age limits. In addition to obtaining Increased Life Status (ILS) from the AAR, the car owner must also apply to the Federal Railroad Administration for authorization to operate the cars beyond the 50-year limit of the FRA Freight Car Safety Standards. This paper will demonstrate the approval process, including AFT testing, as applied to two groups of flat cars in auto rack service, and a group of 60-foot flat cars.
9
Plainer, Markus, Christian Kral, and Gu¨nter Singer. "Investigation of the Longitudinal Dynamic Effects Before and After the Derailment of a Freight Train." In ASME/IEEE 2004 Joint Rail Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/rtd2004-66023.
Повний текст джерелаАнотація:
So far, some freight cars have a detection device attached in order to be able to detect a derailed car. This work was carried out in order to investigate the possibility of the detection of derailments only by means of the evaluation of various signals at the locomotive. Several cases of short trains were examined, both by simulation and in reality. For each train configuration a derailed car at the end of the train and the normally running train were investigated. For these cases the longitudinal forces in the train were simulated and compared with the measured results. Also a long train consisting of 39 cars was examined, but only in simulation. Such a long train could not be derailed in reality. Experiments including the derailment have been carried out by the Austrian Federal Railways. Subsequently, several computer simulations have been performed to check if it is possible to detect a derailed freight car in any distance from the locomotive. Computer simulations have been performed by means of ITI-SIM PC [1]. This software is a block oriented tool for modelling, analysis and optimization of dynamically stressed complex nonlinear systems in the area of machinery and vehicular and mechanical transmission.
10
Huang, Wei, and Yan Liu. "Unsafe Hunting of Freight Rail Cars." In 2009 Joint Rail Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/jrc2009-63042.
Повний текст джерелаАнотація:
Hunting of rail vehicles refers to self-excited oscillation of truck and carbody. This dynamic instability is due to the conicity of the wheels, the wheel/rail creep forces and the action of the suspensions. Hunting increases wheel/rail wear, causes damage to sensitive lading and in extreme cases can throw the track out of geometry. Furthermore, severe hunting can create unsafe operating conditions that lead to derailments. Although it is widely recognized that truck hunting is not a good thing, it is a fact that many thousands of trucks do hunt on any given day but the number of derailments from hunting are few. So when is the hunting unsafe? Database and parametric studies of unsafe hunting are presented in this paper. The FRA database was used to study the hunting derailments by year, car type, track, speed, load condition, weather and temperature. Parametric studies of hunting and unsafe hunting of three-piece freight cars were conducted based on a large number of measured wheel profiles in combination with worn and new rail profiles. The vehicle, track and operational factors that have the major influence on unsafe hunting are analyzed and the conditions of unsafe hunting presented.