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This study aims to investigate the effect of time-varying passenger flow on the wheel wear of metro vehicles to provide a more accurate model for predicting wheel wear and a new idea for reducing wheel wear.

Sectional passage flow data were collected from an operational metro line. A wheel wear simulation based on time-varying passenger flow was performed via the SIMPACK software to obtain the worn wheel profile and wear distribution. The simulation involves the following models: vehicle system dynamics model, wheel-track rolling contact model, wheel wear model and variable load application model. Later, the simulation results were compared with those obtained under the traditional constant load condition and the measured wear data.

For different distances traveled by the metro vehicle, the simulated wheel profile and wear distribution under the variable load remained closer to the measurements than those obtained under the constant load. As the distance traveled increased, the depth and position of maximum wear and wear growth rate under the variable load tended to approach the corresponding measured values. In contrast, the simulation results under the constant load differed greatly from the measured values. This suggests that the model accuracy under the variable load was significantly improved and the simulation results can offer a more accurate basis for wear prediction.

These results will help to predict wheel wear more accurately and provide a new idea for simulating wheel wear of metro vehicles. At the same time, measures for reducing wheel wear were discussed from the perspective of passenger flow changes.

Existing research on the wheel wear of metro vehicles is mainly based on the constant load condition, which is quite different from the variable load condition where the passenger flow in real vehicles varies over time. A method of simulating wheel wear based on time-varying load is proposed in this paper. The proposed method shows a great improvement in simulation accuracy compared to traditional methods and can provide a more accurate basis for wear prediction and wheel repair.

Cutting tool wear is known to affect tool life, surface quality, cutting forces and production time. Micro-milling of difficult-to-cut materials like Inconel 718 leads to significant flank wear on the cutting tool. To ensure the respect of final part specifications and to study cutting forces and tool catastrophic failure, flank wear (VB) has to be controlled. This paper aims to achieve flank wear prediction during micro-milling process, which fills the void of the commercial finite element software.

Based on tool geometry structure and DEFORM finite element simulation, flank wear of the micro tool during micro-milling process is obtained. Finally, experiments of micro-milling Inconel 718 validate the accuracy of the proposed method for predicting flank wear of the micro tool during micro-milling Inconel 718.

A new prediction method for flank wear of the micro tool during micro-milling Inconel 718 based on the assumption that the wear volume can be assumed as a cone-shaped body is proposed. Compared with the existing experiment techniques for predicting tool wear during micro-milling process, the proposed method is simple to operate and is cost-effective. The existing finite element investigations on micro tool wear prediction mainly focus on micro tool axial wear depth, which affects size accuracy of machined workpiece seriously.

The research can provide significant knowledge on the usage of finite element method in predicting tool wear condition during micro-milling process. In addition, the method presented in this paper can provide support for studying the effect of tool flank wear on cutting forces during micro-milling process.

This paper aims to investigate the effect of frictional heat on the wear of high-speed rotary lip seals in engines.

In this research paper, the authors focus on the high-speed rotating lip seal of aircraft engines. Using the hybrid lubrication theory, a thermal-fluid-solid coupled numerical simulation model is established to investigate the influence of parameters such as contact pressure distribution, temperature rise and leakage rate on the sealing performance under different operating conditions. By incorporating the Rhee wear theory and combining simulation results with experimental data, a method for predicting the wear of the rotating seal lip profile is proposed. Experimental validation is conducted using a high-speed rotating test rig.

The results indicate that as the speed increases, the rise in frictional heat leads to a decrease in the sealing performance of the lip seal contact region. The experimental results show a similar trend to the numerical simulation results, and considering the effect of frictional heat, the predicted wear of the lip seal profile aligns more closely with the actual wear curve. This highlights the importance of considering the influence of frictional heat in the analysis of rotating seal mechanisms.

This study provides a reference for the prediction of wear profiles of engine high-speed rotary lip seals.

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.

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.

This paper aims to present the methodology to determine Archard’s wear coefficient. By applying this coefficient into the numerical simulation of wear, it is possible to predict wear without long lasting and usually expensive experiments.

To determine necessary particles of Archard’s equation and calculate wear coefficient K, an experimental investigation is proposed. Afterwards, the wear simulation is executed in FEM software ANSYS 18.1. Analytical method is offered to determine worn volume for cylinder-in-cylinder contact, based on “inclination” of inner cylinder.

Comparing the value of Archard’s coefficient obtained by this experimental investigation with the values from the literature for the similar materials, high correlation is noted. Furthermore, numerically calculated contact pressure is confirmed with analytical method. Trend of pressure decrease due to wearing process, as well as due to increase of contact surface is observed.

Since the prediction of the wear is closely related to the life cycle assessment of bearings, and the machines in general, it has significant practical importance for designers.

Determination of Archard’s coefficient is usually performed by conventional pin-on-disk tribometers. This methodology offers a different approach for the determination of Archard’s wear coefficient for cylinder-in-cylinder contact, which is convenient for shaft-sliding bearing contact.

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.

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 purpose of this paper is to build a transient wear prediction model of surface topography of textured work roll, and then to investigate the wear performance of different original textured surfaces. The surface topography of steel sheets is one of the most important surface quality indexes, which is inherited from the textured work rolls in cold rolling. Surface topography of work roll is obviously changing in the cold rolling process. However, surface topography is difficult to measure in the industry production process.

This paper presents a numerical approach to simulate the wear process based on the mixed lubrication model of cold rolling interface developed by Wilson and Sheu (Sheu and Wilson, 1994). It is assumed that wear takes place at locations where the surfaces are in direct contact, and the volume is removed by an abrasive particle which is an abstract concept based on the wear phenomenon of textured work roll. At each simulation cycle, the distribution of the contact pressure is calculated by the lubrication model. The material is removed by an abstract abrasive particle and the surface topography is modified correspondingly. The renewed surface topography is then used for the next cycle.

Through comparative analysis, it can be found that the simulation results possess similar statistical characteristic with the measured data. A set of roughness parameters such as the amplitude, spacing and frequency-domain characteristics are introduced to analyze the wear performance of different textured surfaces. Numerical examples show that the surface topography has a significant effect on the wear performance of work roll in cold rolling.

The proposed model can accurately predict the wear process of the surface topography in the cold rolling process, which provides the foundation for optimization of original surface topography of textured work roll. The model can also be considered as a tool applicable for research on control of the surface topography of steel strip in the cold rolling process.

This study aims to investigate the erosion wear rate of a stainless steel automobile exhaust manifold, both computationally and physically.

The experiment was performed on a motorcycle exhaust manifold as well as on a 3D model, created using SolidWorks 2022 CAD software. The analysis was later achieved using ANSYS 19.2 simulation software using Fluent – code.

The analysis of solid particle erosion in the exhaust manifold revealed that erosion wear is concentrated predominantly at the extrados of the manifold, with the most significant wear occurring at the lowermost bend. The erosion wear rate increases with larger particulate sizes and varies among bends, with negligible wear observed in straight pipes. The SEM analysis further confirmed surface degradation, with rugged textures, pits and grooves indicating abrasive wear. Spine-like structures and fractured soot particles suggest erosive and abrasive forces caused by high-speed contact of exhaust gas compounds. Energy dispersive X-ray spectroscopy revealed significant carbon abundance, indicating carbonaceous compounds from fuel combustion, along with notable amounts of oxygen and iron, typical of oxidized metallic constituents. The discrete phase modeling (DPM) analysis highlighted peak particulate matter deposition at the first bend exit, with maximum concentrations observed at specific angles. This deposition is influenced by centrifugal force, leading to increased PM concentration at outer bend walls. Velocity magnitude contours showed asymmetrical flow profiles, with high turbulence levels and secondary flow induced by centrifugal effects in bend areas. Dynamic pressure contours revealed varying pressures at intrados and extrados, with maximum pressure observed at the intrados of the manifold’s bends. These findings provide valuable insights into erosion wear, particulate dispersion and flow dynamics within the exhaust manifold.

The study investigated an automobile exhaust manifold model using ANSYS Fluent code and DPM to analyze erosion wear rate phenomena and its various constituents. This analysis was conducted in comparison with a physically eroded sample. The study offers insights into the mechanism underlying the exhaust manifold of an automobile.