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This article substantiates the possibility of solving a difficult task to offer a reliable estimate of the residual resource of the power plant of a hybrid car, which is exposed during operation to the influence of a complex set of external factors. This task is solved by monitoring the time change of diagnostic parameters and controlling the load–speed mode of the hybrid power plant, as well as using physical and chemical processes that cause the degradation of the traction battery. Methodological principles for assessing the resource of a hybrid power plant of a car have been developed, which are based on the disclosure of cause-and-effect relationships between realized and nominal quality indicators, operating conditions, and indicators of technical condition. The choice of rational solutions for the operation of a hybrid car is given, and the external conditions are determined, under which the residual life of the hybrid power plant will change. The scientific result of the study is a theoretical generalization of the scientific provisions of forecasting the resource of the hybrid power plant of a car. This ensures the efficient use of hybrid vehicles and reduces maintenance costs. [ABSTRACT FROM AUTHOR]

Higher efficiency of rail transportation at the present stage of development of the transport industry necessitates the creation and introduction of rail vehicles with improved technical and economic characteristics among which is reduced tare weight. The issue of reducing the tare weight of wagons is quite urgent. It deals not only with the sprung mass of the wagon but also with the load on the rail track, which is under the influence of constant cyclic loads. Therefore, the present study deals with the development of a wagon covered with tarpaulin for carrying goods requiring protection against the environment. The loads inherent for operation on 1520 mm gauge lines are considered. The covered wagon mod. 11-217 is chosen as a prototype. The profiles of the covered wagon frame components are selected according to the moment of resistance of their cross-sections. It is found that the proposed design has a 16% lower tare weight than that of the prototype. The results of the strength calculation for the wagon under the main design operating modes have proved the feasibility of its structural design. The motion of the covered wagon over a track irregularity has been assessed as 'excellent'. The results of the study will contribute to the creation of recommendations for the development of modern structures of covered wagons as well as improve the efficiency of railway transportation. [ABSTRACT FROM AUTHOR]

Rail transport has been the leading sector of the whole transport network. In order to improve the efficiency of its functioning, it is important to develop measures that may help reduce the maintenance cost. To improve the open wagon hatch door strength, it is proposed to make it with rectangular corrugations. The results of calculations show that, taking into account the proposed solution, the weight of the improved hatch door is almost 10% lower than the weight of a typical one. The strength of the hatch door under static loads was calculated. The results of calculations show that the strength of the hatch door under the diagrams considered is ensured. The study will contribute to the development of best practices for modern structures of railway vehicles and increase their cost-effective operation. [ABSTRACT FROM AUTHOR]

Striving to increase the speed of rail vehicles and thus improve the comfort of traveling passengers at the same time, undertakes activities in the sphere of ensuring an appropriate level of safety of rail, passenger, and freight transport. One of the elements of activities in this area is the training of train drivers. Until recently, this training consisted of a theoretical and practical part on the vehicle, alongside an experienced train driver. Considering the increasing level of automation of railway traffic control systems and locomotive equipment, as well as training costs and requirements related to the introduction of TSI, it is becoming an increasingly common requirement to conduct practical training on railway vehicle traffic simulators, while the conditions in the simulator cabin and the trainee's feelings should correspond to the actual driving conditions. A locomotive driving simulator is a system consisting of a cabin of a suitable type of locomotive or EMU, mapped in 1:1 scale, coupled with a motion excitation system and computer programs connected together forming the software of the cab visualization and dynamics system. The basic program simulating the dynamics and kinematics of the cabin's motion is a program containing a motion dynamics model that generates signals forcing the movement of the exciters on which the cabin's platform is mounted. The correct operation of the simulation model depends on the created mathematical model, which can be built in several ways. This article presents the issue of building a mathematical model describing the dynamics of the rail vehicle motion, which can then be used in the simulation model of the simulator cabin motion. Two ways of proceeding in the process of approaching the construction of a mathematical model of rail vehicle motion dynamics will be presented, with the possibility of later use in creating a simulation model of the motion of the locomotive simulator cabin. One of the possible routes was used in the past in the construction of the EP09 locomotive simulator. [ABSTRACT FROM AUTHOR]

This article highlights the structural features of the detachable module for the transportation of long cargoes. The choice of profiles for the detachable module was based on the resistance moments of its components. The detachable module was considered a rod structure on four supports. To determine the longitudinal loads acting on the detachable module, mathematical modeling of its longitudinal dynamics was carried out, provided they were placed on a flat car during a shunting impact. The accelerations obtained were used for the calculations of the detachable module. This article presents the results of the strength calculation of the detachable module under asymmetric loading diagrams, i.e., the action of longitudinal and lateral forces on the detachable module structure. The results of the calculations show that the maximum stresses in the structure of the detachable module when it receives longitudinal loads are 7.7% lower than the permissible ones, and when it receives lateral loads, they are 5.8% lower. Thus, the strength of the detachable module is maintained under the loading diagrams considered. This study also included a modal analysis of the detachable module structure. The first natural frequency of oscillations is found to be 20 Hz. Thus, the safety of the detachable module movement in terms of frequency analysis is ensured. This research will help to create recommendations for the design of modern modular vehicles and improve the efficiency of the transport industry. [ABSTRACT FROM AUTHOR]

The analysis of the statistical values of wear of brake pads in operation, based on which a wear model was developed, is presented in this paper. This model can be used for predicting the remaining service life of brake pads according to the wagon mileage. The distribution function of wear on the upper and lower parts of the pad was determined, which made it possible to find the main qualitative characteristics, namely, the wear intensity, the γ-percentage wear, and the average pad wear at a specified wagon mileage. The results of the study can be factored for solving complex engineering problems of excessive wear of composite brake pads used for freight rolling stock; they could also help to extend the guaranteed overhaul period and improve the railway traffic safety. [ABSTRACT FROM AUTHOR]

The features of designing the frame of a universal container made of square pipes are presented in this paper. The two frame loading schemes are taken into account: the effect of vertical loading on the container frame when it is lifted by the upper corner fittings (I loading mode); the effect of longitudinal loading on the frame during transportation by the rail transport (II loading mode). Mathematical modeling was performed to determine the longitudinal loading acting on the container in the II loading mode. The determined acceleration is taken into account when constructing the schemes of force factors that arise in the frame. The strength of the frame was calculated using the finite element method, which was implemented in SolidWorks Simulation. The conducted research could contribute to creation of recommendations and developments regarding the design of modern structures of modular vehicles. [ABSTRACT FROM AUTHOR]

This article presents the results of a study focused on identifying the main causes of the asymmetric (clinodual) wear of composite brake pads on freight wagons. A new scientific approach to determining the clinodual wear of composite brake pads on freight wagons is proposed. It is established that the harmful abrasion of the pad occurs during the movement of the freight train due to an imperfection in the bogie-brake lever transmission. The causes of the non-normative frictional wear of composite brake pads were investigated. This kind of wear leads to the tilting and abutting of the upper end of the brake pads against the rotating wheel during train running. The results of geometric and kinetostatic studies of the "pad–wheel" tribotechnical pair are provided to establish the causes and consequences of the accelerated clinodual frictional wear of composite brake pads on pendulum suspension in the bogies of freight wagons. The conditions of rotation of the wheels during braking "for" and "against" the clockwise direction depending on the direction of the train are considered. A new approach to brake-pad-wear prediction depending on the mileage of wagons under operational conditions is proposed. The research conducted in this study contributes to the development of the mechanical parts of freight-wagon brakes, increasing the efficiency of brake operation and improving the safety of train traffic. [ABSTRACT FROM AUTHOR]

The paper highlights the results of determining the strength of the brake pad of a freight wagon under uneven loading in operation. The main reasons for the uneven loading on the pad have been found. A mathematical tool for determining the strength of the pad unevenly loaded has been proposed. In the study, the pad is considered to be a rod system loaded with concentrated forces and bending moments. Sensors have been used in order to detect the load state of the brake pads. These sensors have been defined in the simulation software, and they have been placed on the working surface of the pad in the area of its interaction with the wheel. The operation of these sensors was simulated in the simulation software package. The results of the calculation have shown that the stresses in the pad are about 21.1 MPa; thus, they exceed the permissible values by 29%. Therefore, considering the uneven loading of the pad in operation, the strength of the pad is not ensured. To test the obtained results, the strength of the pad was determined using the finite element method. The Coulomb criterion was used for the calculation. It was found that the maximum stresses in the pad were about 19 MPa. These stresses were 21% higher than permissible values and occurred in the back of the pad. The study has proven that the uneven loading on the brake pad in operation can cause their destruction during braking. This may also cause traffic accidents with freight trains during their movement. The results of this study will contribute to the theoretical developments and recommendations aimed at improving the brake system of a freight wagon and rail traffic safety. It is considered that the tensometric sensors will be applied in future experimental tests for comparison and verification of the achieved results from the simulation computations. [ABSTRACT FROM AUTHOR]

The work highlights the results of a study into the dual wedge-shaped wear of composite brake pads for freight wagons. It has been found that the overnormative wear makes the area of a composite brake pad larger in the lower part up to a value directly proportional to the wagon mileage and smaller in the upper part. To assess the braking efficiency of a rail vehicle, a graphical analytical method has been developed; it allows determining the factor of dual wedge-shaped wear of pads depending on the wagon mileage. The results of calculation were verified by comparing two samplings obtained by mathematical and computer modelling. The results of calculation have proven that the hypothesis on the adequacy is not rejected. The results of the study conducted will allow more accurate assessment of the braking efficiency of freight rolling stock to be made, as well as contribute to improving the safety of train traffic. [ABSTRACT FROM AUTHOR]

This article presents the determination of the bearing structure loads of an open car during ro-ro transportation. A special solution for an open car is the application of elastic, viscous honeycomb panels in the frame. This engineering solution can decrease the load of the bearing structure of an open car during interactions with multiple-use lashing devices. This article presents the mathematic modelling of the dynamic load of an open car during ro-ro transportation. This calculation is based on the most popular load diagrams for the bearing structure of an open car applied for sea transportation, namely the rolling motion and the turning motion of a train ferry approaching a dock. It was found that the application of honeycomb panels can decrease the dynamic load of a rail car in comparison to a standard structure by about 25%. The results of the strength calculation of the bearing structure of an open car demonstrated that the maximum equivalent stresses do not exceed the allowable values and are 30% lower than the stresses that emerging in the standard structure. The conducted research can be used by engineers who are concerned about safe and environmentally friendly transportation via train ferries and more efficient ro-ro transportation. [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]

The publication presents the results of research into the strength of an improved tank container. The tare of a tank container can be reduced through application of composite material for the tank. In this case its mass can be 46% lower than that of a metal tank. The strength of the tank was calculated by computer simulation. The maximum stress occurs in its lower part and is about 295 MPa. The dynamic loading of a tank can be reduced by application of elastic elements in the fittings of a tank container. The reduction in dynamic load is achieved by the elastic friction forces generated in the fittings. The results of mathematical modelling of the tank container dynamics proved the effectiveness of this solution. [ABSTRACT FROM AUTHOR]

The article is devoted to the use of Park's vector method for operational control of the rotor condition of induction motors of traction and auxiliary drives of railway rolling stock. In the course of the analysis, it was established that in order to increase the reliability and efficiency of the operation of vehicles, it is necessary to improve and implement diagnostic systems for monitoring the current state of the most damaged elements of induction electric motors built into the drive. This paper presents the development of a new approach to monitoring the state of a squirrel-cage rotor, which is based on the use of Park's vector approach. In the course of the research, the issue of taking into account the asymmetric power supply of the engine during the diagnostic period during industrial operation was solved, which affects the accuracy of determining the degree of damage to the rotor. On the basis of the conducted research, the algorithm of the module for diagnosing the state of the squirrel-cage rotor of an induction motor has been developed for practical use in the built-in on-board systems of vehicles, which allows us to determine the degree of damage and monitor the development of the rotor defect during operation, including in automated mode. [ABSTRACT FROM AUTHOR]

The object of the research is the processes of thermal stress, perception and redistribution of loads by the brake composite pad during braking of the car in operation. In the current conditions, wedge-dual wear of composite brake pads is observed in the braking systems of freight cars, the feature of which is the deterioration of the braking efficiency of freight trains. With this type of wear, both an increase in the load on the brake pad and an «underuse» of the amount of pressure on it can occur. A comprehensive thermal calculation was carried out for composite brake pads with uniform and wedge-dual wear. The results of the calculation showed that the amount of pressure on an abnormally worn pad is 23.3 % less than that acting on a pad with nominal values. It has been proven that the change in the pressure force on the composite pad with different values of the wear parameters during braking leads to a change in the braking force that occurs between the wheel and the rail during braking. The calculation of the strength of the composite brake pad with wedge-dual wear was carried out. The obtained results will make it possible to develop measures to modernize the elements of the brake lever transmission of freight cars. The field of practical use of the obtained results is car-building enterprises. The conditions for the practical use of the results are the brake lever transmissions of carriages of cars with a gauge of 1520 mm. The conducted studies prove the negative impact of wedge-dual wear not only on braking efficiency, but also on the strength of brake pads. This makes it necessary to create measures aimed at its elimination, which will contribute to increasing the level of train traffic safety and significantly reducing the operational costs of maintaining freight cars. [ABSTRACT FROM AUTHOR]

When modelling the dynamics of a rail vehicle ride, one of the important input parameters is the profile geometry of the wheel and rail treads. Commonly available simulation programs have databases containing some standardized profiles, or allow the profile to be added to the database. However, complications arise when a specific profile is required in the simulation analysis. Its geometry must be entered in the form of coordinates of the knot points that can be used to render the curve and thus define the desired profile. Simulation programs, however, do not have the ability to efficiently generate these coordinates. Since this is a lengthy process, the author team has created a program to define this profiles, based on their common drawing documentation. This program allows to create even large amount of profiles needed for variable rail treads definitions of crossings and switch points by a smart way.

The article deals with one of the ways of profile geometry design of a railway wheel and rail. The base for the creation of a new profile is an interactive attitude based on the modification of „the original shape which is defined by section of a railway wheel profile“, with to each other connected and exactly defined arcs radii. It is possible to change them according to shape needs of the final geometrical characteristics. Problems of the railway wheel/rail contact represents a basic point of any analysis which is connected with the moment of a railway vehicle on a track, with safety, speed, with comfort of people and goods transport. It is connected with the construction of new railway vehicles, with the reconstruction the old ones, with the approval (refusal) of vehicles into operation, with their evaluation as well as with the evaluation of track quality and their maintenance. It has a direct influence on the position of rail transport in the frame of the whole transport system, on economics, ecology and so on.

The study deals with a shunting impact of 13-4085 wagon platform to a TK25 tank container. In order to define the loads acting on the container frame, 3D computer models of the 1СС size container is designed, both version – for liquid and dry material transport. The virtual model consider a longitudinal force from the wagon automatic coupling, vertical and horizontal forces from the wagon – containers interaction and also vertical forces of the container fittings. For checking adequacy of the created models, the container acceleration values was obtained in two scenarios. In the first case, when fittings are aligned relative to the fitting spots of a wagon, thus without possibility of relative movement. In the second case, movement within clearance of fitting spots is possible. Mathematical models of dynamic loads on these structures were solved by MathCad. Differential equations were solved by the Runge – Kutta method. Adequacy of the created models was checked with an F-test. On the basis of conducted calculation can be conclude that the hypothesis on the adequacy of the models was not rejected.

In the article the results of studies of loading of the bearing structure of a wagon-platform of an articulated type, created on the basis of the existing construction, during transportation on the railway ferry by sea are given. In order to ensure the reliability of the fixing of the bearing structure of the wagon-platform of the articulated type relative to the deck of the railway ferry, it is proposed to equip it with knots for fixing the chain ties. To study the dynamic loading of a wagon-platform of an articulated type during transportation on a railway ferry by sea, constructed a mathematical model of oscillations with angular displacements relative to the longitudinal axis of the vessel (loll/heel). The maximal values of accelerations, as components of dynamic load, acting on the bearing structure of a wagon-platform are determined. The obtained acceleration values are taken into account when calculating the strength of the bearing structure using the finite element method implemented in the CosmosWorks software environment. It is established that the maximum equivalent tension do not exceed permissible values. The carried out researches will promote increase of efficiency of combined transportations in the direction of the international transport corridors.

The geometric relation between a wheelset and a rail is assessed with the help of geometric characteristics. Geometric characteristics are: equivalent conicity function, delta r function placement of contact points of a wheelset and a rail, tangent gamma function and effective conicity. It turned out that these characteristics are at present the most important not only for the judgment of ride characteristics of a vehicle on the rail but also for the wearing of wheel treads and rail heads, e. i., for the assessment of the track and vehicles in order to find out the current state and for the assessment of changes of the wheels and rails profile shapes in order to improve the current state too. The process of geometric characteristic assessment of a wheelset and rail with regard to wheelset rolling, as well as contact forces are analysed in the article.

The geometric relation between a wheelset and a rail is assessed with the help of geometric characteristics. Geometric characteristics are: equivalent conicity function, delta r function placement of contact points of a wheelset and a rail, tangent gamma function and effective conicity. It turned out that these characteristics are at present the most important not only for the judgment of ride characteristics of a vehicle on the rail but also for the wearing of wheel treads and rail heads, i.e., for the assessment of the track and vehicles in order to find out the current state and for the assessment of changes of the wheels and rails profile shapes in order to improve the current state too. The process of geometric characteristic assessment of a wheelset and rail with regard to angle of attack, as well as contact forces are analysed in the article.

In urban railway environments, the problem of tramcars passing small radius arches appears to be topical. In this regard, the authors proposed that the wheelsets should be complemented on the outer side of the wheels with a second tread of a lower radius, intended exclusively for ride in arches of the track with a radius which the conventional wheelsets cannot even theoretically pass without creep. The complemented wheel tread enters into operation (or out of action) as a result of passing over a specially shaped rail located in the intersections before and behind the small radius arc. In this process, there is a change in the wheel-rail contact location similar to what is commonly used when riding on a facing rail located in the immediate vicinity of the point frog. The paper deals with the comparison of these two cases based on a simulation analysis of vehicle ride. It can be evaluated, that changing the contact point when entering the arc by means of the proposed rails takes place in a more favourable way. It is possible to assume nearly 4 times longer service life of the proposed shaped rail than the one of a frog point.

The peculiarities of organization and perspectives of mass passenger transportation in the city and beyond are considered with the use of "Bus Rapid Transport" (BRT) or Metrobus. Different aspects of study of motor vehicles (MV) controllability and stability are analyzed. It is substantiated that it is sufficient to consider the potential stability of the MV itself, in order to guarantee the stability of the "driver MV" system with a large reserve. A mathematical model of a three-axle bus train consisting of a bus and two trains (metrobus) is developed and the factors influencing the critical speed as the main index of the stability of its movement are determined. It is established that the increase of the critical speed of the metrobus can be achieved by increasing the base of the bus, the first and the second trailer, as well as the mass of the bus and the coefficients of resistance of the drive wheels of the bus driving axle and the trailers axles. At the same time, increasing the distance from the mass center to the bus rear axle, increasing the distance from the mass center to the point of the coupling of the bus with the first trailer, increasing the mass of trailers and the resistance of the resistance of the wheel drive of the bus axis lead to a decrease in the critical speed of the metrobus. This must be taken into account both when designing metrobuses, and when operating them.

The increasing demand for container transportation makes it necessary to equip the wagon fleet with appropriate flatcars in good technical condition. The study deals with the determination of the strength of the flatcar during shunting impacts using the finite element method. The flatcar model 13-401 modernized with fixed fittings for securing containers on the frame was used as a prototype. The authors determined the fields of the maximum equivalent stresses in the bearing structure of a flatcar. The strength calculation was made in SolidWorks Simulation. It was found that, during a shunting collision, the maximum equivalent stresses to the flatcar were about 418 MPa and they were concentrated in the fixed fittings. The strength was also studied using the method of electric strain gauging. The research included different impact speeds. The test results showed that the maximum difference between the stresses obtained theoretically and experimentally was 17.0%. The strength model of the flatcar was tested using the Fisher criterion. The study demonstrated that the damage to the bearing structure of the flatcar and containers could be reduced when applying an improved interaction diagram. [ABSTRACT FROM AUTHOR]

The article presents the results of the strength analysis of the chain binder components for symmetry fixing a wagon on the railway ferry deck, taking into account the actual hydrometeorological conditions of the navigation area. The simulation of the wagon dynamic load during the railway ferry rolling was carried out to determine the loads acting on the chain binder. The strength of the chain binder hook was analysed. The calculation results showed that the maximum equivalent stresses in the hook occur in the radial part and exceed the allowable ones by 23%. Therefore, to ensure the strength of the chain binder, it is necessary to comply with the appropriate roll angles of the railway ferry or create measures to reduce its load when rolling. The conducted studies will contribute to ensuring the safety of wagon transportation by sea and increasing the efficiency of rail-ferry transportation. [ABSTRACT FROM AUTHOR]

The work presents the results of a statistical analysis of random processes of the coefficient of vertical dynamics of a passenger car variation. To determine the dynamic performance of cars the tests were running on the tracks of JSC "Ukrzaliznytsia". The main statistical characteristics of random processes are determined for various modes of car movement along curved and straight sections of the track. As a result of statistical processing of experimental data, correlation functions have been constructed that characterize the degree of connection between different time sections of the process of changing the coefficient of vertical dynamics. The obtained indicators of the law of distribution of the vertical dynamics coefficient values, approximating the models of correlation functions and the numerical values of their parameters, make it possible to further simulate the process of loading a passenger car without carrying out lengthy expensive tests. [ABSTRACT FROM AUTHOR]

This research investigates the stability of a two-wheeled vehicle model on the basis of numerical determination of full range of eigenvalues of a linear approximation matrix in the vicinity of the rectilinear driving mode. The received result was checked by numerical integration of the initial equations system of the disturbed motion of the model. The discrepancy of two research techniques is explained by the specialty of the considered mathematical model in which two pairs of complex conjugate eigenvalues close to each other are realized, that explains the emergence of standard derivations at calculating their numerical determination. The model is asymptotically stable in the range much wider than an operational interval (up to 100 m/s). In order to provide more intensive dampening of initial disturbances, it is possible to introduce additional resilient and damping elements between the trucks and the body in the design of the wheeled vehicle that will counteract the yaw mode of trucks.

Tramways in cities often ride in track curves of a small radius, which is followed by an increased effect of the vehicle on the track. In the rail - wheel contact often occurs creep in longitudinal as well as in lateral direction, which causes increase of riding resistance, wear in rail – wheel contact and noise operation. Exactly with the aim to reduce these undesirable effects we designed a tram bogie with steered wheelsets and with the double wheel tread. This inventions are registered by authors under Utility Model Nr. u201609015 and Patent Application Nr. a201701589. Description of proposed process of passing vehicle through strongly curved track is given in this paper. A comparison of creep velocities in rail - wheel contact results obtained by computer multibody simulations for a tram vehicle riding through a S-curve are presented. Purposefulness of proposed invention is investigated by constructing vehicle ride resistance dependence to the track curve radius.

The article presents the results of determining the equivalent conicity characterizing the geometric interaction of wheels and rails on 1520 mm track. The cases of interactions of rails and wheelsets, wheels of which have different profiles, are considered. The computer model of the motion speed of the passenger car is developed. According to the results of computer simulation, critical speeds for the bogie moving through the tracks of indented gauge are received. Based on the results of the simulation analysis, the significant dependence of the value of the equivalent conicity on the critical speed is confirmed. The necessity of considering the limit values of equivalent conicity in tests of high-speed rolling stock is emphasized.

The mathematical modelling of the dynamic loading of the container-tank during maneuvering collision of the flat wagon has made it possible to obtain an accurate value of the accelerations acting on its supporting structure. At the same time, possible movements of the tank-container relative to the frame of the flat wagons due to the presence of a technological gap in the pair “fitting stop-fitting” are taken into account. It is established that this acceleration, which is a component of the dynamic load, exceeds the one permitted by the regulatory documents. A computer simulation of the dynamic loading of the tank container in the CosmosWorks software environment was also carried out. The calculation was carried out using the finite element method. The results of the simulation made it possible to determine the distribution fields of the accelerations acting on the supporting structure of the tank-container during the shunting of the flat wagon, as well as their numerical values. Checking the adequacy of the mathematical and computer models using the Fisher criterion allowed us to conclude that the hypothesis of adequacy is not rejected.

This paper describes the problem of rising temperature of the friction elements during braking. Negative influence of brake pads heating on the vehicle efficiency and traffic safety is well known. Methods of temperature stabilization in the contact of tribological elements during braking are proposed. Variants of brake pad application with additional elements consisting of phase transition material are considered. Their effectiveness is estimated. The effect of the contact characteristics on noise generation is analysed. The method of noise reduction is considered. The target function for the tribological processes management in the contact of the brake elements has been developed. The application of this target function allows using the braking reserve with the achievement of maximum braking effect with minimal wear and noise.

The article deals with the results of the simulation analysis of a railway wagon bogie model. We analysed four freight wagon bogie variants for its dynamics properties research. The bogie models correspond in general to the Y25 bogie concept. The models were created in SIMPACK software enhanced by the RAIL module. From the research results depicted in the graphs we found out, that the newly designed bogie variant gives the best results when compared to the other analysed versions. The newly designed model consists of a standard Y25 bogie frame with two Lenoire friction dampers. This bogie is equipped with longitudinal linkages on both sides. These linkages are completed with a radial torsion binding, torsion rod, between side bogie parts. The contact of railway wheels and rails generates active forces affecting the surface contact, affecting the size of the normal and tangential stress, wear surfaces of the wheel/rail, or directly the size of the derailment.

The dynamic loading of the bearing structure of the flat wagon from round pipes was investigated during transportation on the railway ferry. The main types of movements of the railway ferry with wagons located on its decks are taken into account. The research has been carried out on the strength of the bearing structure of the flat wagon by the finite element method. The coefficient of the reserve for the fatigue strength of the bearing structure is calculated, taking into account the action of cyclic loads in the conditions of sea disturbance.

The article is devoted to the analysis of the dynamic characteristics of the mechanical system composed of rigid bodies mutually connected with flexible bindings that represent springs and dampers. The analysed system represents the rail vehicle, which is distinguished by the contact link between the wheel and rail, or wheelsets and the track. Currently, analyses of similar type are carried out basically by using commercially distributed software packages, where you enter inputs (which the input forms allow) and the user may achieve results respecting the handling procedures. In accordance with the different approaches to solutions of partial solutions of the issue, the results of the simulations can differ. In the article the theoretical analysis is conducted the parameters of calculation are set out and the results are compared with the results obtained from the calculation by SIMPACK.

For Tram cars, it is often necessary to operate in cities on strongly curved track, which is followed by an increased effect of the vehicle on the track. Especially, this increased effect occurs in spiral transition curves situated between direct and arc sections or between two arc sections of different radius. In such case, increased guiding forces, creep in the rail - wheel contact, wear and noise generation can be observed. Exactly with the aim to reduce these undesirable effects we designed a tram bogie with steered wheelsets. This paper deals with a modification of its coupling to vehicle body in order to improve vehicle dynamics in transition curves. Proposed innovative construction of this coupling unit is registered by authors under Utility Model Nr. u201609015 and Utility Model Nr. u201703246. Description of the proposed way for a vehicle to pass through curved track with regard to bogie-body coupling and wheelset steering mechanisms with usage of multibody computing software is given in this paper.

The paper discusses the preconditions of the methodology development of diagnosis system for assessing dynamic impact of the rolling stock on the basis of processing and analysis of data obtained in operation on the results of measurement of parameters that characterize dynamic vibration processes of the mechanical system of “rolling stock – track”. On the basis of usage of the processing methods of time series and stochastic processes there has been established the relationship between these dynamic processes and wheel defects, and designed experimental data processing algorithms, which in the future will be an integral part of the intellectual systems of decision making when assessing the impact level of the rolling stock on the track. The article presents some results of the experimental and theoretical research of the rail accelerations data, which have been registered during passing of the train. The computational algorithm of the specialized pre-processing of the multidimensional signal recorded by this system is described. The advantage of this algorithm is that it does not require additional information about the train speed on the section equipped with the monitoring system, about the number of wheel pairs of locomotives and train cars, and about the distances between the wheel pairs. Based on the processing results of accelerations of the rails there have been set the parameters of increase in all statistical indicators with increase in the train speed. It is noted that the level of indicators for accelerations of the rails in the vertical direction is twice as high as the corresponding parameters in the horizontal direction.

It is proposed to improve hopper wagon design to provide the possibility of simultaneous transportation of different types of cargo. This improvement consists of dividing the body into two separate sections, interacting with each other through a vertical wall and horizontal connecting belts. A calculation by using the FEM in the SolidWorks Simulation has been carried out to determine the strength of the construction of the two-section hopper wagon. The results of the research showed that the maximum load of the hopper wagon occurs in the first design mode (impact). However, the obtained stresses were lower than permissible by 30%. To calculate the indicators of the wagon dynamics, modeling was carried out. All received dynamics indicators were within the permissible limits. For transporting a hopper wagon on railway ferries in international traffic, it is suggested to use units for the fastening chain. Research of the dynamic load of the hopper wagon supporting structure was carried out through mathematical modeling. The strength analysis of the hopper-wagon-bearing structure was carried out. It was found out that the stresses in the hopper wagon structure did not exceed the normative values. The results of the research will contribute to the increased profitability of railway transport. Additionally, the results of the work can be useful in the creation of modern designs of wagons, including for international traffic. [ABSTRACT FROM AUTHOR]

In the work, studies were carried out on the use of vibration diagnostic methods for monitoring the state of induction motors with a squirrel-cage rotor, operated in electric drives of transport equipment. The most common and difficult-todiagnose damage to an induction motor is turn-to-turn short circuits in the stator winding, which require timely determination and establishment of the degree of damage to prevent an emergency shutdown of the equipment. The main purpose of the study is to establish the most effective areas of application of vibration diagnostic methods in determining the technical condition of the stator of induction motors under load. The experiments were carried out using simulation modeling for cases of turn-to-turn short circuits in one and two phases simultaneously, as well as with the influence of a low-quality supply voltage system on vibration parameters. The results of the work are relevant for further improvement of systems for diagnostic control of drives of transport equipment to increase the efficiency and reliability of their work. [ABSTRACT FROM AUTHOR]

The article presents the results of the strength calculation of the FLAT RACK removable module design using the finite element method. The FLAT RACK removable module provides higher efficiency of freight transportation. The special features of the removable module are its components made of rectangular tubes and its fittings with viscoelastic bonds. The parameters of the profile for such a removable module are determined through the maximum resistance moments of its components. The research includes mathematical modelling of the dynamic loading on the removable module placed on a flat wagon during a shunting impact. The accelerations to the removable module are also determined. The results are confirmed by computer modelling of the dynamic loading on the removable module. It is found that the strength of the removable module is provided. The research conducted may be used by those who are concerned about designing advanced module-type rail vehicle structures and enhancing their operational efficiency. [ABSTRACT FROM AUTHOR]

The mathematical model of a multi-section articulated bus has been improved in the article, which allowed to determine the stability indicators of the two and three-section articulated buses for the Metrobus system. The critical speed for the three-section articulated bus was 28.06 m/s and for the two-section articulated bus - 30.89 m/s. Since the motion of multi-section articulated buses will be carried out on separate lanes with a speed of 25 - 28 m/s, one can assume that the stability of rectilinear traffic of both two and three-section buses is provided. In non-stationary modes of motion with two-section articulated buses, the lateral speed of the first bus decreases by almost 8.5 % compared to the three-section and the second trailer-bus increases by almost 9.5 % compared to the three-section. In this case, the motion stability of multi-section articulated buses can be considered satisfactory, as the lateral accelerations in the center of mass of all sections do not exceed 0.45 g. [ABSTRACT FROM AUTHOR]

A one-dimensional thermal problem of friction was formulated, taking into account the contact pressure increase at the beginning of the process. The obtained solution to this problem allows for the quick calculation of the transient temperature distribution in a railway brake disc during single braking application. In order to validate the developed model, the experimental tests were performed for two friction pairs consisting of the cast iron brake disc and pads comprising two composite materials. Theoretical results were compared with the data measured by thermocouples embedded in the brake disc during the full-size dynamometer tests. The maximum temperature values found based on the analytical solution are convergent with the corresponding empirical data. The consistency of the results obtained for two friction couples demonstrates the usefulness of the proposed computational model. [ABSTRACT FROM AUTHOR]