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The purpose of this paper is to study the wear evolution of metro wheels under the conditions of different track sequences, track composition and vehicle load and then to predict wheel wear and to guide its maintenance.

By using the SIMPACK and MATLAB software, numerical simulation analysis of metro wheel wear is carried out based on Hertz theory, the FASTSIM algorithm and the Archard model. First of all, the vehicle dynamics model is established to calculate the motion relationship and external forces of wheel-rail in the SIMPACK software. Then, the normal force of wheel-rail is solved based on Hertz theory, and the tangential force of wheel-rail is calculated based on the FASTSIM algorithm through the MATLAB software. Next, in the MATLAB software, the wheel wear is calculated based on the Archard model, and a new wheel profile is obtained. Finally, the new wheel profile is re-input into the vehicle system dynamics model in the SIMPACK software to carry out cyclic calculation of wear.

The results show that the setting order of different curves has an obvious influence on wear when the proportion of the straight track and the curve is fixed. With the increase in running mileage, the severe wear zone is shifted from tread to flange root under the condition of the sequence-type track, but the wheel wear distribution is basically stable for the unit-type track, and their wear growth rates become closer. In the tracks with different straight-curved ratio, the more proportion the curved tracks occupy, the closer the severe wear zone is shifted to flange root. At the same time, an increase in weight of the vehicle load will aggravate the wheel wear, but it will not change the distribution of wheel wear. Compared with the measured data of one city B type metro in China, the numerical simulation results of wheel wear are nearly the same with the measured data.

These results will be helpful for metro tracks planning and can predict the trend of wheel wear, which has significant importance for the vehicle to do the repair operation. At the same time, the security risks of the vehicle are decreased economically and effectively.

At present, many scholars have studied the influence of metro tracks on wheel wear, but mainly focused on a straight line or a certain radius curve and neglected the influence of track sequence and track composition. This study is the first to examine the influence of track sequence on metro wheel wear by comparing the sequence-type track and unit-type track. The results show that the track sequence has a great influence on the wear distribution. At the same time, the influence of track composition on wheel wear is studied by comparing different straight-curve ratio tracks; therefore, wheel wear can be predicted integrally under different track conditions.

Conventional wear models cannot satisfy the requirements of electrical contact wear simulation. Therefore, this study aims to establish a novel wear simulation model that considered the influence of thermal-stress-wear interaction to achieve high accuracy under various current conditions, especially high current.

The proposed electrical contact wear model was established by combining oxidation theory and the modified Archard wear model. The wear subroutine was written in FORTRAN, and adaptive mesh technology was used to update the wear depth. The simulation results were compared with the experimental results and the typically used stress-wear model. The temperature of the contact surface, distribution of the wear depth and evolution of the wear rate were analyzed.

With the increase in the current flow, the linear relationship between the wear depth and time changed to the parabola. Electrical contact wear occurred in two stages, namely, acceleration and stability stages. In the acceleration stage, the wear rate increased continuously because of the influence of material hardness reduction and oxidation loss.

In previous wear simulation models, the influence of multiple physical fields in friction and wear has been typically ignored. In this study, the oxidation loss during electrical contact wear was considered, and the thermo-stress-wear complete coupling method was used to analyze the wear process.

Quantitative fretting wear prediction is of practical significance for industrial components. This study aims to establish a fretting wear model considering the formation of tribolayers and provide better fretting wear prediction.

Based on the characteristics for the formation of tribolayers, the ratio of fretting amplitude to nominal contact area length in the fretting direction is used to characterize their formation and contribution to the wear volume. The wear volume is then associated with the product of the friction energy and the ratio of fretting amplitude to nominal contact area length.

Better prediction in the wear volume can be achieved with the proposed fretting wear model by taking the formation of tribolayers into consideration.

The contribution of the formation of tribolayers to the wear volume is considered in the model and better prediction can be achieved.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2023-0004/

Considering that a meet between high-speed trains can generate aerodynamic loads, this study aims to investigate the effect of high-speed train meet on wheel wear at different speeds to provide a more accurate wheel wear model and a new idea for reducing wheel wear.

The train speed was set at 250, 300, 350 and 400 km/h separately, and a vehicle system dynamics model was constructed using the parameters of an actual high-speed train on a line. The aerodynamic forces arising from constant-speed train meet were then applied as additional excitation. Semi-Hertzian theory and Kalker’s simplified theory were used to solve the wheel/rail contact problems. The wheel wear was calculated using Archard wear model. The effect of train meet on wheel wear was analyzed for the whole train, different cars and different axles.

According to the results, all wheels show a wear increase in the case of one train meet, compared to the case of no train meet. At 250, 300, 350 and 400 km/h, the total wheel wear increases by 4.45%, 4.91%, 7.57% and 5.71%, respectively, over the entire operational period. The change in speed has a greater impact on wheel wear increase in the head and tail cars than in the middle car. Moreover, the average wear increase in front-axle wheels is 1.04–2.09 times that in rear-axle wheels on the same bogie.

The results will help to analyze wheel wear more accurately and provide theoretical guidance for wheel repair and maintenance from the perspective of high-speed train meet.

At present, there is a lot of focus on the impact of high-speed train meet on the dynamic performance of vehicles. However, little research is available on the influence of train meet on wheel wear. In this study, a vehicle dynamics model was constructed and the aerodynamic forces generated during high-speed train meet were applied as additional excitation. The effect of train meet on wheel wear was analyzed for the whole train, different cars and different axles. The proposed method can provide a more accurate basis for wear prediction and wheel repair.

Oblique impacts which occur in many situations in mineral industries leads to material removal and fail of mechanical parts. Studies will be helpful in optimal design to have minimum machine malfunctions.

In the present work, the Hertz-Di Maio Di Renzo nonlinear model of contact is used to simulate the impact phenomenon as a micro-sliding process. The modified Archard equation is used to evaluate wear over the impact. The wear coefficient is evaluated by a pin-disk machine. An impact-wear tester is used to validate the model results.

The measurements indicate an increase in surface hardness because of the several impacts. It is considered in the wear predictive model.

The model predictions compared with the experimental data, obtained from the impact-wear tester, show that the model well predicts the impact wear and can be used as a predictive tool to study the practical design problems and to explain some phenomena associated with the percussive impact.

This paper aims to present the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of elastohydrodynamic lubrication (EHL), according to the cam wear prediction using Archard’s model. Cam–follower kinematic pairs always work under wear because of concentrated contacts. Given that a cam and follower contact often operates in the mixed or boundary lubrication regime, simulation of cam wear is a multidisciplinary problem including kinematic considerations, dynamic load and stress calculations and elastohydrodynamic film thickness evaluations.

Multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL are applied to obtain the dynamic loads, the time histories of contact pressure and the oil film thicknesses in cam–follower conjunctions to predict cam wear quantitatively.

The wear depth of the cam in the valve train of a heavy-load diesel engine is calculated, which is in good agreement with the measured value in the practical test. The results show that the cam–tappet pair operates under a mixed lubrication or boundary lubrication, and the wear depths on both sides of the cam nose are extremely great. The wear of these points can be decreased significantly by modifying the local cam profile to enlarge the radii of curvature.

The main value of this work lies in the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL, which can give good prediction for the wear of cam.

The inchworm actuator is widely applied in space industry. One of the major issues in space instrumentation is the reliability, especially under space thermal load. The purpose of this paper is to present a numerical calculation method for the inchworm actuator reliability with considering the effect of space temperature.

First, the structure of designed inchworm actuator is introduced, and the main failure reason is analyzed. Then the wear model is proposed with considering the space temperature, and an experiment device is designed to verify the wear model. Finally, the reliability calculation method is developed based on the working principle of the inchworm actuator.

The numerical calculation method can be applied to calculate the reliability of the inchworm actuator with considering the space temperature. And the results provide a new perspective to discuss the influences of the temperature and driving voltage on the reliability of inchworm actuators.

This work presents a reliability calculation method of inchworm actuators with considering the space temperature.

With the help of multi-body dynamics software UM, the paper uses Kik–Piotrowski model to simulate wheel-rail contact and Archard wear model for rail wear.

The CRH5 vehicle-track coupling dynamics model is constructed for the wear study of rails of small radius curves, namely 200 and 350 m in Guangzhou East EMU Depot and those 250 and 300 m radius in Taiyuan South EMU Depot.

Results show that the rail wear at the straight-circle point, the curve center point and the circle-straight point follows the order of center point > the circle-straight point > the straight-circle point. The wear on rail of small radius curves intensifies with the rise of running speed, and the wearing trend tends to fasten as the curve radius declines. The maximum rail wear of the inner rail can reach 2.29 mm, while that of the outer rail, 10.11 mm.

With the increase of the train passing number, the wear range tends to expand. The rail wear decreases with the increase of the curve radius. The dynamic response of vehicle increases with the increase of rail wear, among which the derailment coefficient is affected the most. When the number of passing vehicles reaches 1 million, the derailment coefficient exceeds the limit value, which poses a risk of derailment.

Friction and wear are very important factors in predicting the performance of journal bearings, particularly under heavy load in start-up processes. However, there are few relevant studies on the numerical model. This study aims to establish a transient-mixed lubrication model to predict the performance of journal bearings, focusing on the friction and wear behavior under heavy load during start-up.

The average Reynold equation, three-dimensional energy equation, shear stress model for friction and Archard model for wear are coupled in the transient model by finite difference method. The linear wear simulation method is bought out to reduce the update times and the calculation time.

The different start-up accelerations and linear wear times set are compared and discussed, which indicates a reasonable start-up acceleration is necessary for journal bearings under heavy load during start-up, and setting linear wear times is an effective method to reduce the simulation time significantly. Furthermore, the wear profile in the start-up process spreads in both the clearance and circumferential directions, but mainly in the clearance direction, which increases the minimum film thickness and affects the friction performance.

This study is of great significance for the numerical prediction of the transient performance of journal bearings during start-up considering friction and wear.

Sliding wear is a common phenomenon in the iron ore handling industry. Large-scale handling of iron ore bulk-solids causes a high amount of volume loss from the surfaces of bulk-solids-handling equipment. Predicting the sliding wear volume from equipment surfaces is beneficial for efficient maintenance of worn equipment. Recently, the discrete element method (DEM) simulations have been utilised to predict the wear by bulk-solids. However, the sensitivity of wear prediction subjected to DEM parameters has not been systemically investigated at single particle level. To ensure the wear predictions by DEM are accurate and stable, this study aims to conduct the sensitivity analysis at the single particle level.

In this research, pin-on-disc wear tests are modelled to predict the sliding wear by individual iron ore particles. The Hertz–Mindlin (no slip) contact model is implemented to simulate interactions between particle (pin) and geometry (disc). To quantify the wear from geometry surface, a sliding wear equation derived from Archard’s wear model is adopted in the DEM simulations. The accuracy of the pin-on-disc wear test simulation is assessed by comparing the predicted wear volume with that of the theoretical calculation. The stability is evaluated by repetitive tests of a reference case. At the steady-state wear, the sensitivity analysis is done by predicting sliding wear volumes using the parameter values determined by iron ore-handling conditions. This research is carried out using the software EDEM^® 2.7.1.

Numerical errors occur when a particle passes a joint side of geometry meshes. However, this influence is negligible compared to total wear volume of a wear revolution. A reference case study demonstrates that accurate and stable results of sliding wear volume can be achieved. For the sliding wear at steady state, increasing particle density or radius causes more wear, whereas, by contrast, particle Poisson’s ratio, particle shear modulus, geometry mesh size, rotating speed, coefficient of restitution and time step have no impact on wear volume. As expected, increasing indentation force results in a proportional increase. For maintaining wear characteristic and reducing simulation time, the geometry mesh size is recommended. To further reduce simulation time, it is inappropriate using lower particle shear modulus. However, the maximum time step can be increased to 187% T_R without compromising simulation accuracy.

The applied coefficient of sliding wear is determined based on theoretical and experimental studies of a spherical head of iron ore particle. To predict realistic volume loss in the iron ore-handling industry, this coefficient should be experimentally determined by taking into account the non-spherical shapes of iron ore particles.

The effects of DEM parameters on sliding wear are revealed, enabling the selections of adequate values to predict sliding wear in the iron ore-handling industry.

The accuracy and stability to predict sliding wear by using EDEM^® 2.7.1 are verified. Besides, this research accelerates the calibration of sliding wear prediction by DEM.