Influence of Suspension Parameters Changes of a Railway Vehicle on Output Quantities (original) (raw)

An Investigation of the Influence of the Suspension Construction Parameters on the Performances of the Railway Vehicles

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...

Assessment of the influence of the elastic properties of rail vehicle suspensions on safety, ride quality and track fatigue

Vehicle System Dynamics, 2013

A sensitivity analysis has been performed to assess the influence of the elastic properties of railway vehicle suspensions on the vehicle dynamic behaviour. To do this, 144 dynamic simulations were performed modifying, one at a time, the stiffness and damping coefficients, of the primary and secondary suspensions. Three values were assigned to each parameter, corresponding to the percentiles 10, 50 and 90 of a data set stored in a database of railway vehicles.After processing the results of these simulations, the analyzed parameters were sorted by increasing influence. It was also found which of these parameters could be estimated with a lesser degree of accuracy in future simulations without appreciably affecting the simulation results. In general terms, it was concluded that the highest influences were found for the longitudinal stiffness and the lateral stiffness of the primary suspension, and the lowest influences for the vertical stiffness and the vertical damping of the primary suspension, with the parameters of the secondary suspension showing intermediate influences between them.

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.

Identification of the technical state of suspension elements in railway systems

Vehicle System Dynamics, 2012

The running safety and passenger comfort levels in a vehicle are tightly related to the technical state of the suspension elements. The technical state of the suspension depends of the service life time as its components become old and wear out. In this paper, a study on the dynamic behaviour of a railway vehicle is established in relation to the damping elements in one of its suspension stages. An experimental measurement model is developed, obtaining a set of useful signals for the identification of the dynamic parameters of the vehicle and developing a test through the application of the operational modal analysis technique, using least-squares complex exponential method as a basis to validate the numerical model of the multi-body system. Then, the study focuses on developing numerical simulations for the identification of the technical state of the dampers by the registration of dynamic variables under commercial service conditions and on estimating the state of the suspension elements.

Adaptation of Rail Passenger Car Suspension Parameters to Independently Rotating Wheels

Transport Problems, 2022

This study aimed to adjust the rail passenger car running gear parameters by adapting them to independently rotating wheels. The most important aspect was the safety of the passenger car running in terms of derailment; thus, the values of the Nadal criterion were calculated first. Another aspect to consider is passenger comfort based on the values of Sperling’s comfort index according to the rail passenger car speed. The modes of suspension behaviour during operation were considered in two typical conditions: on a straight track section and on a curve with a 200-m radius. Calculations were performed using Universal Mechanism software. The results are interpreted in the paper, and the final conclusions of this study are given.

Dynamic Analysis and Experimental Investigation for Vibration Response of Suspension System of Indian Railway Vehicle

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.

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.

Possible experimental method to determine the suspension parameters in a simplified model of a passenger car

International Journal of Automotive Technology, 2012

−Currently, as well as in the past, researchers have shown great interest in developing suspension systems for vehicles and especially in the design and optimization of the suspension parameters, such as the stiffness and the damping coefficient. These parameters are considered to be important factors that have an influence on safety and improve the comfort of the passengers in the vehicle. This paper describes a simplified methodology to determine, in a quick manner, the suspension parameters for different types of passenger cars equipped with passive suspension systems. Currently, different types of passenger cars are produced with different types of suspension systems. Finding a simplified methodology to determine these parameters with sufficient accuracy would contribute a simplified and quick method to the inspection of the working conditions of a suspension system. Therefore, a simple system to determine these parameters is needed. An analysis of the suspension parameters is performed using mathematical modeling and numerical analysis conducted using the Working Model software. The result derived from the developed methodology shows small errors when compared with the generic values, and it can be concluded that the design of the suspension parameter measurement device using the developed methodology is useful, simple, and has sufficient accuracy.

Analysis of vehicle’s suspension's dynamic responses during test track rides and real exploitation

2018

The following paper presents a study of dynamic responses of a passenger vehicle in typical exploitation conditions. It describes the process of acquiring data from the test rides and their further analysis using statistical values using MatLab. The analysis focuses on accelerations of sprung and unsprung mass, suspension deflection and its speed, comparing the values achieved on different road surfaces, taking into account safety limits and suspension characteristic. The data acquired are presented as graphs of density of probability and cumulative empirical probability, as well as tables listing dynamic responses undergoing analysis. The results allow for estimation of expected dynamic responses of a vehicle, thus making the preparation of future experiments more thorough. Keywords:suspension, dynamic responses, kinematic excitation