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The object of the research is the processes of occurrence, perception, and redistribution of loads in the load-bearing structure of an open wagon body, taking into account the use of an intermediate adapter. To reduce the vertical dynamic loads acting on the supporting structure of the railroad car, it is suggested to use an intermediate adapter between the frame and the load. The dynamic load of the supporting structure of the open wagon was modeled, taking into account the use of an intermediate adapter. The research was carried out in the vertical plane during the oscillations of the bouncing of the car. The results of the calculations showed that the acceleration acting in the center of mass of the supporting structure of the open wagon is 4.2 % lower than that acting on the supporting structure of the open wagon without using an adapter. The obtained acceleration results are taken into account when determining the strength of the supporting structure of the open wagon. It was established that the use of an intermediate adapter contributes to the reduction of stresses in the supporting structure of the open wagon by 6 % compared to the typical scheme of cargo transportation. A feature of the results is that the proposed solution to reduce the dynamic load of the supporting structure of the car can be implemented without improving its design. The field of practical use of the results is the engineering industry, in particular, railroad transport. The conditions for the practical use of the research results are the placement of the adapter over the entire floor area of the car body. The research will contribute to devising recommendations on reducing the load on the load-bearing structures of cars, the costs of their unplanned repairs, and to increasing the efficiency of railroad transport operation. [ABSTRACT FROM AUTHOR]

Coupler separation is among the serious accidents threatening the operation safety of heavy-haul trains. This paper reports a study on the formation mechanism and key influencing factors of middle coupler separation of a 20,000-tonne combined heavy-haul train during air-braking release by means of field investigation, theoretical analysis and numerical simulation. The interaction state between the connected coupler knuckles and the potential sensitive factors leading to the coupler separation are investigated based on field tests and theoretical analysis. The formation process of coupler separation and the related influencing factors are analysed through numerical simulations. The results show that the coupler separation between slave locomotives and connected wagons usually occurs in the switching process of the longitudinal coupler force from the buffing (compressive) state to the draw (tensile) state. The excessive initial height difference of connected coupler knuckles, dynamic braking force of locomotive, pitch angle of locomotive and wagon coupler as well as the too small friction coefficient of the coupler knuckles significantly increase the risk of coupler separation. [ABSTRACT FROM AUTHOR]

Suspension system performs the function of reducing the vibration transfer from the track irregularities to the vehicle body and hence to be designed to improve ride performance which can be judged by the comfort of the ride and maintaining contact between wheels and track way for good vehicle handling for any driving condition. Suspension systems can be generally classified into three varieties: passive, active and semi-active. Conventional suspension system consisting of springs and dampers is referred to as passive suspension and suspension system with external control is referred to as a semi-active or active suspension. As part of the study, on a Magneto Rheological (MR) damper, Skyhook, ground hook and hybrid control strategies are tested and compared using MATLAB Simulink simulations. [ABSTRACT FROM AUTHOR]

Increasing the length and hauled mass represents an effective method for boosting freight train transportation. However, several analyses showed that longer and heavier trains pose safety concerns mainly related to large buffer forces generated during emergency braking. The paper investigates the effect of payload sequence on these forces referring to freight trains for intermodal transportation. A simplified trainset model is developed to predict the maximum buffer forces during emergency braking, for a set of 500 trains generated with random payload distribution. An optimisation algorithm developed for combinatorial problems is then applied to change the payload sequence on each train so that buffer forces are minimised. Optimised train sequences are then inputted into a more accurate model for longitudinal trainset dynamics, showing that a proper wagon arrangement can decrease buffer forces by more than 40%. The analysis also provided general guidelines for optimising wagon sequence. [ABSTRACT FROM AUTHOR]

Analyses of cargo transport in 2021 show that despite the increased volume of cargo transported by all types of transport compared to 2020, road transport is still dominant compared to rail transport. Therefore, all actions aimed at improving these unfavorable relations (rail transport vs. road transport) in transport, particularly cargo transport, should be considered purposeful and justified. One such activity is the ongoing work on the design and construction of freight wagons for specialized transport. Unlike universal wagons, specialized wagons are characterized by a limited ability to transport a wide range of material groups. An example is the transport of timber. However, the development of new transport technologies, and above all, technical and organizational progress, force the organizers of these transport modes to look for new logistic and rolling stock solutions. The aforementioned transport of timber is an example of this. The transport of wood does not constitute a large volume of transport, but taking into account its transport issues (transport with large truck tractors, high axle loads, and high risks for other road users), it is a classic example of the fact that it should not be carried out by road over long distances. Therefore, all actions aimed at reducing these issues and improving efficiency by using rail transport are desirable and even necessary. The article presents an innovative design solution in the form of a stanchion basket installed on flat wagons, allowing the use of standard wagons of this type to transport both containers and timber as well as loads such as beams and pipes. Such a solution will allow the use of empty runs of these wagons after unloading wood at the destination station for further transport of containers and vice versa. The considerations described in the article show the research process at the construction stage and testing the prototype of the built basket and the wagon with the stanchion basket structure placed on it. [ABSTRACT FROM AUTHOR]

Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: the development of a system for automatic control of car loading, which will be able to combine separate nodes into one common system to ensure greater control and reliability of the process. Research methods are grapho-combinatorial. Methodology: the research is justified by a logical synthesis based on the hardware of embedded control systems, programming in the language of functional blocks of the MEK61131-3 standard. Results: the requirements for the structure of the automation system of coal loading complexes were formulated, the basic automation equipment was selected, and the control algorithms were determined. Based on the requirements for the automation system, a functional scheme and its technical implementation of the automation of coal loading complexes as a single control system were developed. The algorithm was developed and subsequently the SAC program of the local system was developed, which was able to show its performance in the "Owen Logic" environment. This made it possible to adjust and select the correct coefficients and possible calculated data. Scientific novelty: the development of a functional model of the coal loading complex and the use of wireless communications, aimed at combining fragmented local systems into one common one to ensure greater control and reliability of the process. Practical significance: the functional and structural model of the coal loading complex will allow to increase its level of automation, reliability and efficiency of operation, to eliminate the shortcomings of the technical fragmentation of the system and to prevent significant material, time and economic costs for setting up the system. [ABSTRACT FROM AUTHOR]

The present research work aims at providing data on heat transfer by forced convection from three-dimensional bodies suspended in a free stream of air. The shapes investigated covered cubic and rectangular bodies with air flow parallel and normal to the body's axis. The experiments were carried out inside an air duct in which air flows over a model for the three-dimensional body. The results obtained were represented by power function relations between the Nusselt and Reynolds number. The results were divided into the main body axis was parallel to the direction of the air flow. The heat transfer from the whole cube could be broken to the face components. This showed that the sides and rear face were responsible for more heat transfer. Increasing the length of the rectangular body increased the heat transfer. The equation representing the increase of heat transfer with length is suggested. The present results are essential in designing air-conditioned railway coaches, heated liquid wagons, refrigerated cars, and food and fluid carriers. [ABSTRACT FROM AUTHOR]

Traditionally, freight wagon technology has lacked digitalization and advanced monitoring capabilities. This article presents recent advancements in freight wagon digitalization, covering the system's definition, development, and field tests on a commercial line in Sweden. A number of components and systems were installed on board on the freight wagon, leading to the intelligent freight wagon. The digitalization includes the integration of sensors for different functions such as train composition, train integrity, asset monitoring and continuous wagon positioning. Communication capabilities enable data exchange between components, securely stored and transferred to a remote server for access and visualization. Three digitalized freight wagons operated on the Nässjo–Falköping line, equipped with strategically placed monitoring sensors to collect valuable data on wagon performance and railway infrastructure. The field tests showcase the system's potential for detecting faults and anomalies, signifying a significant advancement in freight wagon technology, and contributing to an improvement in freight wagon digitalization and monitoring. The gathered insights demonstrate the system's effectiveness, setting the stage for a comprehensive monitoring solution for railway infrastructures. These advancements promise real-time analysis, anomaly detection, and proactive maintenance, fostering improved efficiency and safety in the domain of freight transportation, while contributing to the enhancement of freight wagon digitalization and supervision. [ABSTRACT FROM AUTHOR]

Couples of heavy-haul freight cars are simulated, using a 62-degree-of-freedom multi-body model developed on Simpack®, running on both tangent track and circular curve under different conditions. A benchmark simulation running at a speed of 70 km/h is set up, and then, different breaking scenarios with 2.5 kN, 5 kN, 7.5 kN and 10 kN of abnormal braking force application are simulated. In this paper, the effect of forces acting on the wheel–rail interface is compared using the derailment coefficient (L/V) and the material wear, defined by energy dissipation (Tγ). For the double-wagon setup placed in various positions along the train, the simulations run under no braking and abnormal braking conditions, where the braking force acts in only one of the wheels of the wheelset. This condition leads to an increase of up to 18% in L/V in one curve and up to 17% of reduction on the curve in the other direction. The wear increases 68% and decreases 71%, depending on the direction of the curve. These effects haven't been associated with longitudinal dynamic effects in previous studies, including in-car shocks and traction forces. [ABSTRACT FROM AUTHOR]

Copyright of Smart Rail Transit is the property of Smart Rail Transit Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Smart Rail Transit is the property of Smart Rail Transit Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Scientific Bulletin of National Mining University is the property of National Mining University, State Higher Educational Institution and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: During an excavation of a Bronze Age, Füzesabony‐culture cemetery at Encs (north‐eastern Hungary), a clay wagon model with spoked wheels (grave 1290) and three miniature solid clay wheels were found (grave 1389). Miniature wagon and wheel models in burials began to appear in the Late Copper Age and lasted until the Iron Age in Central Europe. Their presence allows of several interpretations. These spoked wheels of grave 1290 provide early evidence about the appearance of such in the Carpathian Basin. Focussing on the two graves from Encs, this article reports AMS radiocarbon dates that suggest the spoked wheels belong to the early second millennium BC. The implications of these finds are interpreted though a comparative review of both wagon models from the Füzesabony culture and the evidence for early spoked wheels in the Carpathian Basin. [ABSTRACT FROM AUTHOR]

Dust emissions resulting from handling and transporting particulate materials are a problem in the mining industry. These emissions are more accentuated when the materials are not very humid because the reduced humidity makes the particles lighter and more susceptible to dispersion. Faced with these issues, this study proposes a methodology for the theoretical and experimental study of the drying process that occurs when iron ore fines are transported in wagons. The objective is to clarify the effect of surface moisture in the process of dragging wind iron ores on moist surfaces, such as those found when transporting iron ore in open wagons. In this study, wind tunnel tests were carried out using a wagon model with fine iron ore. A numerical CFD model was developed, and the results agreed well with the experimental results. The numerical model allowed the evaluation of the drying behavior for different values of air flow velocity and the prediction of the thermal conditions that influence the drying process. [ABSTRACT FROM AUTHOR]

Increased volumes of freight turnover in international transportation require the situational adaptation of the existing wagon fleet to the transportation of containers, which are commonly used at present. The research presented in this article substantiates the possibility of transporting containers in open wagons. It has been found that taking into account the possible displacements of containers in the body, the stresses at the operating modes can be twice as high as the permissible ones if an open wagon is part of the combined train. In this regard, it is proposed that a detachable multifunctional module for securing containers in the open wagon body be used. The detachable module is fixed through the fitting stops, either stationary or hinged, in the body. The rationale for the choice of the detachable module profile, as well as the results of its strength calculation, is given. The strength of the open wagon body during container transportation has been studied taking into account the proposed fastening diagram. The results of the calculations have shown that the maximum stresses in the body do not exceed permissible values. The results of the study will contribute to improvement in the efficiency of container transportation and the transport industry as a whole. Also, these results may be useful developments for designing modular vehicles. [ABSTRACT FROM AUTHOR]

In a railroad wagon, the vertical excitation on the wheels originated from the track irregularities; the air spring model is reliably used to restrict these abnormal vibrations at a required level and improve traveler comfort. When air springs deflate during running, too much vibration occurs and the ride is less comfortable, which are common complaints among high-speed rail operators. In the situation that the air spring deflates, the laminated rubber spring acts as a temporary emergency spring to reduce the dynamic load. An approximation method for measuring laminated rubber's static stiffness is presented and examined the effect on the air suspension. In this study the equations of motion for the pitch, roll, and the bounce motion of the bogies and the car's body were developed with deflated state of air spring to systematically study the effect of deflated air spring on the ride comfort of passengers. The study show that passengers' ride comfort was predicted accurately by the proposed model. It also observed that in the presence of a laminated rubber spring, the air spring's dynamic stiffness is moved to higher frequencies. The air spring's dynamic stiffness is reduced at lower frequency when the diameter of the surge pipe is increased. According to the results of the research, the vehicle's speed should be reduced while the air spring is deflated in order to keep the passengers' comfort. [ABSTRACT FROM AUTHOR]

Crushing is an integral and indispensable process of mineral production, as it adds value to the product by reducing the ore granulometry for subsequent processing in the plant. Bauxite is transported by trains from the storage yards to the shipping port, which requires time and loading efficiency adjustments. Thus, in this study, simulation models of the crushing and loading wagons processes were developed in the Arena® software to validate a mining production system. The loading models presented results close to the real ones and therefore were validated. Crushing models were considered valid for providing consistent results after being tested in different scenarios. [ABSTRACT FROM AUTHOR]

A structural solution was proposed to enable passive control of the wheelsets of a motorised metro car on curved track with a small curve radius. This effect was achieved by varying the stiffness of the guidance of the wheelsets in the horizontal plane of the frame of each bogie on which the wagon body rests. This ensured the required critical speed of the metro wagon when moving on straight track, and allowed for reduced mechanical wheel wear and better steering of the bogies when moving on curved track with a small radius of curvature. Parameters specific to the design of modern metro cars were taken into account. Current knowledge of non-linear lateral dynamics of rail vehicles and the specialist computer programme Vi-Rail were used to perform the calculations involving simulation models. [ABSTRACT FROM AUTHOR]

This paper focuses on the research on regression rate of hybrid rocket motor with single-port wagon wheel fuel grain. Both experiment and numerical investigations are carried out to study the three-dimension regression rate of hybrid rocket motor on several characteristic points. A laboratory 500 N-class firing test of hybrid rocket motor with single-port wagon wheel fuel grain has been conducted on the standard ground experimental system. The 98% hydrogen peroxide oxidizer and hydroxyl terminated polybutadiene based fuel are adopted as propellants. The digital image processing of three-dimension regression rate is carried out, and a post-processing software has been developed to calculate the time-averaged three-dimension distribution of regression rate after the firing test. Three-dimensional numerical simulations with gaseous combustion considered are carried out to study the axial distribution of regression rate. The results of digital image processing manifest that the average regression rates of the middle position of wagon wheel spokes is higher than those in the slot of wagon wheel. A good agreement exists between the calculated regression rate from numerical simulation and the experimental results conducted by computed tomography scanning. The comparison results show that the digital image processing is potentially an effective tool for investigating and predicting the three-dimension regression rate of hybrid rocket motor with single-port wagon wheel fuel grain. • Firing test of HRM with single-port wagon wheel fuel grain has been carried out. • The method of CT scanning digital image processing and software are developed. • Three-dimension regression rates of HRM are characterized by simulation and test. • A good agreement exists between regression rates from simulation and CT scanning. [ABSTRACT FROM AUTHOR]

The present paper shows the development of a strategy for the calculation of the air brake forces of European freight trains. The model is built to upgrade the existing Politecnico di Torino longitudinal train dynamics (LTD) code LTDPoliTo, which was originally unable to account for air brake forces. The proposed model uses an empirical exponential function to calculate the air brake forces during the simulation, while the maximum normal force on the brake friction elements is calculated according to the indication of the vehicle braked weight percentage. Hence, the model does not require to simulate in detail the fluid dynamics in the brake pipe nor to precisely know the main parameters of the braking system mounted on each vehicle. The model parameters are tuned to minimize the difference between the braking distance computed by the LTDPoliTo code and the value prescribed by the UIC 544-1 leaflet in emergency braking operations. Simulations are run for different configurations of freight train compositions including a variable number of Shimmns wagons trailed by an E402B locomotive at the head of the train, as suggested in a reference literature paper. The results of the proposed method are in good agreement with the target braking distances calculated according to the international rules. [ABSTRACT FROM AUTHOR]

Shunting stations play an essential role in ensuring the proper functioning of the railway transport system. The proper organisation of their work allows trains to be dispatched on time and compensates for delays in other areas of the railway network. This paper presents a method for evaluating the technological process of wagon processing at shunting stations based on the author's formulation of evaluation measures and using a simulation model developed in Flexsim. A variant computational example was developed to verify it and demonstrate its capabilities. The method has many applications in assisting decision-makers in organising shunting station operations, adapting the shunting station layout to the tasks or identifying bottlenecks. [ABSTRACT FROM AUTHOR]

The purpose of the work is to study the influence of the longitudinallytransverse shift of the cargo's center of mass on the dynamic loading of the wagon in order to solve the problem of predicting the dynamics and stability of an asymmetrically loaded railroad vehicle. During the analytical simulation, a multibody model of the spatial oscillations of the wagon was used. The differential equations of wagon oscillations are compiled using the d'Alembert principle, while the wagon is considered as a system with 42 degrees of freedom. The work presents the results of analytical simulation of some dynamic processes of interaction of railroad vehicles with the rails on the example of flat wagons. The results of the analytical simulation are presented, taking into account the speed of movement along the curved sections of the railway track. The proposed multibody model "heavy cargo -- wagon" makes it possible to analytically determine the dynamic characteristics of the system and ensure the development of such methods of transportation of heavy cargo that meet the requirements of train traffic safety. The application of the obtained results will help improve the running safety of freight wagons and enhance the technical and economic performance of railways. [ABSTRACT FROM AUTHOR]