Identification of the technical state of suspension elements in railway systems (original) (raw)
Related papers
A vibration analysis of suspension of rail vehicle has to be performed which reflects both the varying load and response. A rail vehicle experiences lateral and vertical effect in very high response due to track imperfection, tractive effort, breaking effort, curving and tracking. The differential equation for vibration analysis gives the time dependent response in the superstructure by including damping forces and inertial forces in the equation and each node is subjected to a sinusoidal function of the peak amplitude for that node. This paper represents the vibration response of rail vehicle having primary and secondary suspension with vertical, lateral and longitudinal damping. At first, the complex structure of dynamics of rail vehicle is to simplify in two mass damper suspension models to solve complex differential equation to find its natural frequency and amplitude. The aim is to check dynamic sinusoidal variations for the failure response of primary suspension spring by finding the natural frequency of model and excitation frequency of rail. The vibration response of two mass suspension systems with base excitation is obtained analytically using differential equation which gives peak amplitude by steady state solution. The mathematical model for increasing complexity i.e. for lateral and roll dynamics has also been developed and vibration analyzer is used to find dynamic behavior of rail vehicle in running condition at an average speed of 80-100 km/hr for number of instances during smooth track, curving and tracking.
GEMI Research Group has developed a series of research projects aimed at innovation, science and technology on the field of railway systems. The knowledge acquired on trains is the basis on which EAFIT University develops research projects, aimed at transport companies and financed by the Administrative Department of Science, Technology and Innovation of the Republic of Colombia. It is in this direction that this work presents the results of the research process focused on the methodology developed for Operation Modal Analysis (OMA) applied to railway systems. The work is structured under the follow themes: (i) methodological proposal, (ii) evaluation criteria of the system, (iii) Experimental Modal Analysis (EMA), (iv) development of numerical models in multi-body theory, (v) validation of the numerical models, (vi) OMA application using Last-Square Complex Exponential method (LSCE), and (vii) presentation of a case study. The work studies the dynamical performance of a railway veh...
Study of the railway vehicle suspension using the multibody method
INCAS BULLETIN, 2009
The article presents a mathematical model for the study of a passenger coach hunting motion using the multibody approach. The model comprises the lateral displacement, rolling and yawing motions for the main constitutive elements: axles, bogies and case. The equation system is written applying energetic methods. The forced vibrations determined by the irregular profile of the tracks are considered. The wheel -rail contact forces are expressed using the creepage coefficients established according to Kalker's linear theory. The equations system is solved through numeric methods using specialized calculus programs. The response of the system -passenger coach on a tangent track, the critical speed and the influence of the constructive characteristics of the coach on its performances are determined.
Influence of Suspension Parameters Changes of a Railway Vehicle on Output Quantities
LOGI – Scientific Journal on Transport and Logistics
This article deals with computer analyses of output quantities of a railway vehicle depending on changing of parameters of suspension system. A passenger car was chosen for dynamic analyses. An analysed passenger railway vehicle uses two stage suspension system composed of coil springs and hydraulic dampers. Stiffness of coil springs of primary and secondary suspensions were defined for two states and its influence on output values in terms of quality and quantity was evaluated. As output variables, values of forces in a wheel/rail contact and accelerations in several locations on a wagon body floor were chosen. Values of forces in a wheel/rail contact indicate dynamic response of a railway vehicle running in terms of running safety and values of accelerations serve as important input for evaluation of passenger ride comfort.
Proceedings of the Romanian Academy - Series A: Mathematics, Physics, Technical Sciences, Information Science
The paper aims to present a study of the construction parameter influence of a railway vehicle suspension on its performances: safety and comfort. To simulate the lateral dynamics of the vehicle is used a multibody model with 17 degrees of freedom. This model considers the lateral, yawing and rolling oscillations, the geometrical nonlinearities of the wheel-track contact and assesses the nonlinear stability of the vehicle running on tangent tracks with irregularities. To reduce the lateral accelerations generated by the track irregularities, the authors introduced in the secondary suspension of the vehicle a device with sequential damping based on balance-logic control strategy and shown that the use of a semi-active suspension improves the safety and the comfort of the railway vehicle. The system response in terms of accelerations is compared for both passive and semi-active cases.
Analysis of primary and secondary lateral suspension system of railway vehicle
Journal of Mechanical Engineering, 2014
The aim of this paper is to study the effect of primary and secondary suspensions of a railway vehicle on stability and passenger ride comfort. The possible improvement of conventional suspension without using a controllable suspension system is investigated. A linear 17 degree-of-freedom (DOF) railway vehicle model is used to study the vibration response of the railway vehicle body. The equations of motion that represent the dynamics of the railway vehicle were derived based on Newton laws to describe the lateral, yaw and roll motions of the vehicle body, bogies and also wheel-sets. The spring stiffnesses and damping coefficients of the primary and secondary suspensions were varied incrementally in order to observe the response of the railway vehicle body. The vehicle model was simulated with lateral sinusoidal track disturbance using Matlab-SIMULINK software. The simulation results showed that the railway vehicle stability is significantly affected by the values of primary suspens...
Modelling and Control of Railway Vehicle Suspensions
Lecture Notes in Control and Information Sciences, 2007
This chapter uses a railway vehicle as an example of a mechanical dynamic system to which control can be applied in a manner that yields significant benefits from an engineering and operational viewpoint. The first part describes the fundamentals of railway vehicles and their dynamics: the normal configuration, the suspension requirements, how they are modelled and an overview of the types of control concept that are currently applied or under consideration. The second part provides a case study of controller design issues.
Operational Modal Analysis and the Performance Assessment of Vehicle Suspension Systems
Shock and Vibration, 2012
Comfort, road holding and safety of passenger cars are mainly influenced by an appropriate design of suspension systems. Improvements of the dynamic behaviour can be achieved by implementing semi-active or active suspension systems. In these cases, the correct design of a well-performing suspension control strategy is of fundamental importance to obtain satisfying results. Operational Modal Analysis allows the experimental structural identification in those that are the real operating conditions: Moving from output-only data, leading to modal models linearised around the more interesting working points and, in the case of controlled systems, providing the needed information for the optimal design and verification of the controller performance. All these characters are needed for the experimental assessment of vehicle suspension systems. In the paper two suspension architectures are considered equipping the same car type. The former is a semi-active commercial system, the latter a no...
2018
The use of inerters in the lateral suspension of railway vehicles has been proven, in recent studies using lumped mass models, to provide benefits in terms of track wear and passenger comfort improvement. Validation of these enhancements using an industry standard simulation tool, which analyses realistic vehicle models with numerous degrees of freedom, is essential if the railway industry is going to adopt this new piece of technology. The problems associated with this, however, come in the form of large complicated numerical matrices, slow inversion times, and algebraic loops associated with the inerter's acceleration dependence. The systematic investigation of candidate vibration absorber configurations is also problematic. To this end, this paper proposes a Location Matrix method of simulation which enables the optimisation of interchangeable suspension networks within large dynamic systems by the use of a Laplace to state-space transformation. This method, which can be applied to any dynamic system and needs only the knowledge of the base mass, stiffness and damping matrices, is validated using a low degree of freedom system, and it is found that for railway vehicles, optimisation on a linearised or semi-linearised model can be performed. Nonlinearities arising from the varying contact patch normal force mean that further investigation is needed before a full analysis can take place.
Vehicle System Dynamics, 2013
Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/nvsd20 Vehicle System Dynamics, 2013 Vol. 51, No. 5, 700-720, http://dx.Reliability of the railway vehicle suspension system is of critical importance to the safety of the vehicle. On-line health condition monitoring for the suspension system of rail vehicles offers a number of benefits such as preventing further deterioration of vehicle performance, enhancing vehicle safety, increasing operational reliability and availability, and reducing maintenance costs. It is desirable to timely detect the fault and monitor the performance degradation of vehicle suspension systems. In this paper, a comparative study on fault detection methods of urban rail vehicle suspension systems is considered. A novel sensor configuration is proposed where the underlying vehicle system is equipped with only acceleration sensors in the four corners of the carbody, the leading and trailing bogie, respectively. A mathematical model is developed for the considered vehicle suspension system. Both model-based and data-driven approaches are studied for the suspension fault detection problem. The robust observer, the Kalman filter combined with the generalised likelihood ratio test method, the dynamical principle components analysis and the canonical variate analysis approaches are applied to the fault detection problem. The simulation is carried out by means of the professional multibody simulation tool, SIMPACK. In addition, the advantages and disadvantages of these methods are compared. The simulation results show that the data-driven methods outperform the model-based methods.