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Showing 1 to 19 of 19 for “"wheel-rail contact"”.
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A Statistical Approach to Modeling Wheel-Rail Contact Dynamics
The wheel-rail contact mechanics and dynamics that are of great importance to the railroad industry are evaluated by applying statistical methods to the large volume of data that is collected on the VT-FRA state-of-the-art roller rig. The intent is to use the statistical principles to highlight the …
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Wheel-rail contact force reconstruction using trackside measurements and inverse models
Railway condition monitoring is a fundamental aspect that influences operational safety, costs and efficiency. Wheel-rail contact forces, specifically vertical wheel-rail contact forces provide crucial information that can be further analysed and used by decision makers of railway operators to …
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Multiple model based real time estimation of wheel-rail contact conditions
The issue of low adhesion between the wheel and the rail has been a problem for thedesign and operation of the railway vehicles. The level of adhesion can be influenced bymany different factors, such as contamination, climate, and vegetation, and it isextremely difficult to predict with certainty. …
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The Influence of Wheel-Rail Contact Forces on The Formation of Rail Shells
Made available in DSpace on 2014-12-10T22:21:38Z (GMT). No. of bitstreams: 1 7121177.pdf: 3858784 bytes, checksum: 634993734117af2b287810b920041c7b (MD5) Previous issue date: 1971
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Investigation of the finite element method for computing wheel/rail contact forces in steady curving
The understanding of rail vehicle steady-state and dynamic curving has increased substantially in the last few years. Contemporary curving models include such nonlinear effects as two-point contact, creep force saturation, and rail flexibility. The usual approximation concerning the contact …
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State of the Art Roller Rig for Precise Evaluation of Wheel-Rail Contact Mechanics and Dynamics
… on the development of a state-of-the-art single-wheel roller rig for studying contact mechanics and dynamics in railroad applications. The use of indoor-based simulation tools has become a mainstay in vehicle testing for the automotive and railroad industries. In contrast to field-testing, roller …
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Electromechanical Design and Development of the Virginia Tech Roller Rig Testing Facility for Wheel-rail Contact Mechanics and Dynamics
… sophisticated roller rig testing facility at the Railway Technologies Laboratory (RTL) of Virginia Polytechnic and State University (VT) is presented. The VT Roller Rig is intended for studying the complex dynamics and mechanics at the wheel-rail interface of railway vehicles in a controlled …
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Accurate Wheel-rail Dynamic Measurement using a Scaled Roller Rig
… and constructed by Virginia Tech and the Federal Railroad Administration (VT-FRA Roller Rig). The study also aims at determining the effect of naturally generated third-body layer deposits (because of the wear of the wheel and/or roller) on creep or traction forces. The wheel-rail contact forces, …
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A computational approach to the prediction of wheel wear profiles
Wheel wear profiles are interesting for both economic and performance reasons. A good wheel profile design should be able to resist wear and to allow stable vehicle running. The ability to resist wear reduces the wheel reprofiling and replacement cost. The ability to allow stable vehicle running is …
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Nonlinear Investigation of the Use of Controllable Primary Suspensions to Improve Hunting in Railway Vehicles
Hunting is a very common instability exhibited by rail vehicles operating at high speeds. The hunting phenomenon is a self excited lateral oscillation that is produced by the forward speed of the vehicle and the wheel-rail interactive forces that result from the conicity of the wheel-rail contours …
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Vertical dynamics of railway vehicle-track system
A comprehensive finite element (FE) model of railway vehicle-track system is developed to study the dynamic interaction between the vehicle and track. The vehicle is represented by a lumped parameter system. The track is modeled as a Timoshenko beam on discrete pad-tie-ballast supports. The tie is …
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Effect of Wheel and Rail Conditions on Contact Dynamics and Mechanics
This study uses the Virginia Tech – Federal Railroad Administration (VT-FRA) Roller Rig to assess how different running conditions affect the wheel-rail interface (WRI) dynamics and mechanics under repeatable and precise test settings. The advanced roller rig is used to emulate wheel loads, lateral …
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Implementation of a comprehensive methodology for structural dynamics and NVH simulation incorporating MBS, FEM and ray tracing
… mitigating noise pollution stemming from railroad vehicles is imperative. Manufacturers and operators of rolling stock exhibit a keen interest in simulation tools tailored for calculating acoustic emissions from rails and vehicles. These tools not only furnish robust assistance and …
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Design and Development of Force Control and Automation System for the VT-FRA Roller Rig
… disturbances in the Virginia Tech – Federal Railroad Administration (VT-FRA) Roller Rig. The VT-FRA Roller Rig is a state-of-the-art roller Rig for studying contact mechanics. It consists of a 0.2m diameter wheel and a 1m diameter roller in vertical configuration, which replicates the …
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Prediction of wheel wear profiles by analytical methods
… the prediction of the wear history of a train wheel by a numerical simulation. The method consists of three fundamental steps. First, the wheel/rail contact geometry is characterized. Contact points, Herzian contact patch area and creep coefficients are determined as functions of the wheelset …
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Analytical Evaluation of the Accuracy of Roller Rig Data for Studying Creepage in Rail Vehicles
… a scaled roller rig for accurately assessing the contact mechanics and dynamics between a profiled steel wheel and rail, as is commonly used in rail vehicles. The established creep models of Kalker and Johnson and Vermeulen are used to establish correction factors, scaling factors, and …
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A Polynomial Chaos Approach for Stochastic Modeling of Dynamic Wheel-Rail Friction
… (CoF) is essential to accurately modeling railroad dynamics, reducing maintenance costs, and increasing safety factors in rail operations. The assumption of a constant CoF is popularly used in simulation studies for ease of implementation, however many evidences demonstrated that CoF …
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Condition monitoring of train wheels using a cost-effective smart rail pad
… focuses on the condition monitoring of train wheels utilizing an 3D printed rail pad that is embedded with widely available accelerometers and a strain gauge. This smart rail pad was used on a heavy haul railway line to monitor train wheels by identifying any wheel defects and measuring the …
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Experimentální studium mazání okolku kolejových vozidel
Diplomová práce se zabývá experimentálním studiem vlivu provozních podmínek na tribologické aspekty kontaktu okolku železničního kola a kolejnice. Kontakt okolku nastává při průjezdu vozu traťovým obloukem a dochází v něm k těžkému až katastrofickému režimu opotřebení. Pro efektivní redukci …