Wheel-rail contact friction coefficient is often assumed to be constant through the entire patch for calculation of surface traction. In reality, however, value in a certain point decreases when transitioning from adhesion slip regimes. Including this behaviour estimations traction on can potentially provide more accurate calculations wear and rolling fatigue (RCF). present work, velocity-dependent implemented tangential solver using concept 'Friction Memory'. The effect implementation...

In this article, a wheel life prediction model considering wear and rolling contact fatigue (RCF) is developed applied to heavy-haul locomotive. For calculations, methodology based on Archard's calculation theory used. The simulated depth compared with profile measurements within 100,000 km. RCF, shakedown-based locally, using the FaStrip algorithm estimate tangential stresses instead of FASTSIM. differences between two algorithms damage models are studied. running distance reprofiling due...

A validated overhead conductor rail and a well-known wear model have been programmed to perform closer-to-reality simulations. Reliable rate estimates for two configurations of rails three models pantographs at different speeds supply currents obtained. Results show that decreases with increasing speed high when the distances between supports are uniform. In addition, use types in same facility has positive effect terms reduction. Consequently, an adequate selection operating conditions...

A new methodology to estimate costs for wear and Rolling Contact Fatigue (RCF) on rails that cause a major portion of track maintenance is presented. It demonstrated standard UIC-Y25 bogie the FR8RAIL bogie, softer cross-braced iteration former, based running conditions Swedish iron-ore line. Various non-linearities in vehicle models have been considered. The rail profile evolution surface-initiated fatigue surface different radii with progressive tonnage are calculated using iterative...

A successful predictive maintenance strategy for wheels and rails depends on an accurate robust modelling of damage evolution, mainly uniform wear Rolling Contact Fatigue (RCF). In this work a life prediction framework is presented. The model accounts wear, RCF, their interaction based the output from MBS simulations to calculate remaining asset, given in mileage MGTs rails. Once calibrated, proposed methodology can predict sensitivity intervals against changes operational conditions, such...

Abstract There are several fatigue-based approaches that estimate the evolution of rolling contact fatigue (RCF) on rails over time and built to be used in tandem with multi-body simulations vehicle dynamics. However, most models not directly comparable each other since they based different physical even though shall predict same RCF damage at end. This article studies quantifying puts forward a measure for degree agreement between them. The methodological framework various steps...

The present paper describes an active centring system for railway vehicles. proposed solution is based on lateral pneumatic actuators placed between bogie and car body connected to the vertical secondary suspension air springs. objective of developed twofold: improvement curving behaviour train decrease acceleration perceived by passenger in curve negotiation thanks reduction 'souplesse' coefficient. described detail paper. Results from simulations are included considering a bidimensional...

In railway applications wear prediction in the wheel–rail interface is a fundamental matter order to study problems such as wheel lifespan and evolution of vehicle dynamic characteristic with time. However, one principal drawbacks existing methodologies for calculating computational cost. This paper proposes new methodology reduced based on two main steps: first substitution calculations over whole network by calculation contact conditions certain point from whose result can be inferred. The...

Wheel reprofiling costs for freight vehicles are a major issue in Sweden, reducing the profitability of traffic operations and therefore hindering modal shift needed achieving reduced emissions. In order to understand damage modes vehicles, uniform wear prediction with Archard's law has been studied two-axle timber transport wagon, simulation results have compared measurements. Challenges wheel wagons discussed, including influence block brakes switches crossings. The latter on profile...

The renewal costs for wheels and rails are a substantial part of the rolling stock operators infrastructure managers all over world. causes reprofiling or grinding are, in most cases, related to following: (1) wheel rail profiles with unacceptable wear, (2) appearance contact fatigue cracks surface, (3) flats caused by locking during braking. first two dynamic behavior vehicle–track system, can be predicted using multibody simulations. However, there several limitations that restrain...

In the benchmark on switches and crossings, simulations have been carried out in different switch configurations operational conditions, with a specified wheel/rail friction coefficient of μ=0.35 considered as dry friction. This means that contamination or third-body layers are not taken into consideration, thus using theoretical creep curve is much steeper than actual curves measured real railways. this paper, we perform comparison between then estimate impact simulated forces when used...

As a general rule, the multi-body simulation models used by railway vehicle designers consider wheelsets to be fully rigid, thus leading possible errors when calculating critical speed of under study. This article suggests wheelset model that takes into account flexibility for study dynamic stability. The is simple implement, easily parameterised, and can applied both conventional variable gauge wheelsets. parameters corresponding most influence high-speed vehicles are also analysed.

Modelling and simulation of wheel profile evolution is a time-consuming process in which the variables that affect cases are usually selected tuned through an iterative process, order to find right setup for specific case. In previous work, fast reliable methodology wear prediction was developed, systematic applicable general terms any arbitrary network, vehicle fleet or operating conditions. Here influence running behaviour along track were classified into two groups (deterministic...

Wheel profile evolution has a large influence on track and wheelset related maintenance costs. It influences important parameters such as equivalent conicity or contact point positioning, which will affect the dynamic behavior of vehicle, in both tangent curve negotiation. High axle loads freight wagons may increase wheel wear damage caused by vehicles with new already worn profiles. A common Europe is S1002 profile, developed for rail inclination 1/40. In Sweden 1/30, so conditions might...

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Abstract This paper presents the implementation of dual extended Kalman filter (DEKF) to estimate wheelset equivalent conicity, an accurate understanding which can facilitate effective model-based estimator. The estimator is developed identify conicity high-speed railway vehicles while negotiating a curve. designed DEKF employs two discrete-time filters combining state and parameter estimators in parallel. uses easily available measurements from acceleration sensors measuring at axle boxes...