The tiny contact zone (approximately 1 cm 2) where steel wheel meets steel rail is fundamental to rail transport this work is a comprehensive presentation of recent research in wheel–rail contact tribology. The objective of this study was to investigate the influence of contaminants on the tribological behavior of wheel–rail contact sand, phosphate, sulfur, and cement were the studied contaminants identified after a tunisian railway expertise. Rolling contact fatigue of railway wheels – rolling contact fatigue in section 3 a model for the fatigue of railway wheels is derived and presented in papers c, d this thesis focusses on rolling contact fatigue of railway wheels 2 p reliminaries – fatigue analysis 3. To this end, the research described in this thesis is twofold: theoretical in which the wheel - rail contact is modelled in terms of contact and friction, and experimental in which the friction between wheel and rail is measured to validate the developed model. The wheel-rail contact force is unknown and has to be determined in the calculations the track can be modelled by finite elements and in many cases a modal analysis of.
Wheel‒rail contact conditions leading to a reduction of wheel–rail contact forces (stresses) and creepages in order to obtain robust optimised solutions that perform well in traffic, the. List of appended papers this thesis consists of a summary and the following appended papers: paper a y zhu, u olofsson, a söderberg: “adhesion modeling in the wheel–rail contact under. Multiple model based real time estimation of wheel-rail contact conditions hussain, i 2012, multiple model based real time estimation of wheel-rail contact conditions, phd thesis, salford: university of salford preview pdf download (28mb) | preview abstract the issue of low adhesion between the wheel and the rail has been a problem for the.
Abstract the wheel–rail contact problem plays an important role in the simulation methods used to solve railway dynamics problems as a consequence, many different mathematical models have been developed to calculate wheel–rail contact forces. Low adhesion in the wheel/rail contact or the ‘leaves on the line’ problem is a large operational issue for the railway industry there is currently a shortage of up to date information about the running conditions of rails with respect to short term adhesion trends (over a daily period) and macro trends (across seasons). Vernersson t tread braking of railway wheels – noise-related tread roughness and dimensioning wheel temperatures phd thesis, chalmers university of technology, sweden, 2006 5 a comparison of analytical and numerical methods for the calculation of temperatures in wheel/rail contact.
13ème congrès de mécanique 11 - 14 avril 2017 (meknès, maroc) a numerical model, based on fem, for obtaining the vertical wheel-rail contact force a zougari1, j martínez2 , r sanchís3 1 2 mechanical engineering department universitat politécnica de catalunya. Wheel–rail dynamics with closely conformal contact part 2: forced response, results and conclusions a bhaskar, k l johnson and j woodhouse engineering department, cambridge university. Influence of wheel/rail contact geometry on large amplitude wheelset equations of motion j dyn sys, meas, control (september, 1981) a random walk model approach for the wheel-rail contact force estimation. Abstract in this investigation, four nonlinear dynamic formulations that can be used in the analysis of the wheel/rail contact are presented, compared and their performance is evaluated. Most available wheel/rail interaction models for the prediction of impact forces caused by wheel flats use a hertzian spring as contact model and do not account for the changes in contact stiffness due to the real three-dimensional wheel flat geometry.
Title master’s thesis presentation chapter 01 chapter 02 chapter 03 chapter 04 chapter 05 wheel rail contact ride quality documents similar to thesis final active vibration control flexible bodied railway vehicles via smart structures uploaded by. Adhesion in the wheel–rail contact yi zhu doctoral thesis department of machine design royal institute of technology se-100 44 stockholm trita – mmk 2013:15 issn 1400-1179 as the wheel–rail contact is an open system, the adhesion between the wheel and rail is inevitably affected by contaminants contaminants, which. This research demonstrates that the output parameters of the wheel–rail contact simulations have a broad deviation and the input variable with the most influence on the contact form and position is the lateral displacement of the wheelset. Abstract friction management and control of adhesion at the wheel/rail interface is vital for an efficient and cost effective railway network the understanding of how the friction management products (grease and friction modifiers) work and effectively test these products is necessary to improve the performance of a railway network.
How to model the wheel rail contact in this thesis different models are presented for the search of the contact location as well as for the normal and the tangential contact problem especially the relation between the contact models and vehicle dynamic simulation is investigated. A on wear transitions in the wheel-rail contact jon sundh doctoral thesis department of machine design royal institute of technology se-100 44 stockholm.
The susceptibility of railway wheels to wear and rolling contact fatigue damage is influenced by the properties of the wheel material these are influenced by the steel composition, wheel manufacturing process, and thermal and mechanical loading during operation. Figure 47 (a) 1a – wheel/rail contact force for the bogie leading wheel (type 1) figure 47 (b) 1a – wheel/rail contact force for the bogie leading wheel (type 1) figure 48 1b – rail bending moment at sleeper a (type 2. Introduction general contact modeling wheel-rail contact analysis computer simulation tools for railway vehicle dynamics future trends sources of further information and advice references. The wheel/rail contact is no exception, where an understanding of interface pressures is essential, as this information is required in both fatigue and wear calculations for the wheels and rails.