Brake Disc Temperature Research Articles

Application of basic machine learning algorithms in railway brake disc temperature prediction

This article is focused on brake disc temperature prediction introducing basic machine learning algorithms to reach this goal. In the first part, the problematics of brake disc frictional heating is described. Next, the methods currently used for predicting/calculating are described as well as their pros and cons. In the following part, some basic machine learning algorithms are described only very briefly, since going into details of theories of those algorithms in this article would extend it significantly. In the last part, the experiment with small dataset is described and its results and future possible work are discussed.

Modeling and simulation of frictional disc/pad interface considering the effects of thermo-mechanical coupling

Purpose This study aims to investigate numerically a thermomechanical behavior of disc brake using ANSYS 11.0 which applies the finite element method (FEM) to solve the transient thermal analysis and the static structural sequentially with the coupled method. Computational fluid dynamics analysis will help the authors in the calculation of the values of the heat transfer (h) that will be exploited in the transient evolution of the brake disc temperatures. Finally, the model resolution allows the authors to visualize other important results of this research such as the deformations and the Von Mises stress on the disc, as well as the contact pressure of the brake pads. Design/methodology/approach A transient finite element analysis (FEA) model was developed to calculate the temperature distribution of the brake rotor with respect to time. A steady-state CFD model was created to obtain convective heat transfer coefficients (HTC) that were used in the FE model. Because HTCs are dependent on temperature, it was necessary to couple the CFD and FEA solutions. A comparison was made between the temperature of full and ventilated brake disc showing the importance of cooling mode in the design of automobile discs. Findings These results are quite in good agreement with those found in reality in the brake discs in service and those that may be encountered before in literature research investigations of which these will be very useful for engineers and in the design field in the vehicle brake system industry. These are then compared to experimental results obtained from literatures that measured ventilated discs surface temperatures to validate the accuracy of the results from this simulation model. Originality/value The novelty of the work is the application of the FEM to solve the thermomechanical problem in which the results of this analysis are in accordance with the realized and in the current life of the braking phenomenon and in the brake discs in service thus with the thermal gradients and the phenomena of damage observed on used discs brake.

Thermomechanical Model for the Analysis of Disc Brake Using the Finite Element Method in Frictional Contact

The braking phenomenon is an aspect of vehicle stopping performance where with kinetic energy due to speed of the vehicle is transformed to thermal energy via the friction between the brake disc and its pads. In our work, we presented numerical modeling using ANSYS software adapted in the finite element method, to follow the evolution of the global temperatures for the two types of brake discs, full and ventilated disc during braking scenario. Also, numerical simulation of the transient thermal and the static structural analysis were performed sequentially, with coupled thermo-structural method. Numerical procedure of calculation relies on important steps such that the Computational Fluid Dynamics and thermal analysis have been well illustrated in 3D, showing the effects of heat distribution over the brake disc. This CFD approach helped in the calculation of values of the heat transfer coefficients (h) that have been exploited in 3D transient evolution of the brake disc temperatures. Three different brake disc materials were tested and comparative analysis of the results was conducted in order, to derive the one with the best thermal behavior. Finally, the resolution of the coupled thermomechanical model allows us to visualize other important results of this research such as; the deformations, and the equivalent Von Mises stress of the disc, as well as the contact pressure of brake pads. Following the analysis of the results obtained, we draw several conclusions from this investigation. The choice allowed us to deliver the excellent rotor design to ensure and guarantee the good braking performance of the vehicles.

Design and Thermomechanical Finite Element Analysis of Frictional Contact Mechanism on Automotive Disc Brake Assembly

The braking phenomenon is an aspect of vehicle stopping performance where with kinetic energy due to speed of vehicle is transformed to thermal energy via the friction between the brake disc and its pads. The heat must then be dissipated into the surrounding structure and into airflow around the brake system. The frictional thermal field during the braking phase between the disc and the brake pads can lead to excessive temperatures. In our work, we presented numerical modeling using ANSYS software adapted in the finite element method, to follow the evolution of the global temperatures for the two types of brake discs, full and ventilated disc during braking scenario. Also, numerical simulation of the transient thermal and static structural analysis was performed here sequentially, with coupled thermo-structural method. Numerical procedure of calculation relies on important steps such that the computational fluid dynamics (CFD) and thermal analysis have been well illustrated in 3D, showing the effects of heat distribution over the brake disc. This CFD analysis helped us in the calculation of the values of the heat transfer coefficients (h) that have been exploited in 3D transient evolution of the brake disc temperatures. Two different rotor designs and three different brake disc materials were tested and comparative analysis of the results was conducted in order, to derive the one with the best thermal behavior. Finally, the resolution of the coupled thermomechanical model allows us to visualize other important results of this research such as the deformations, and the equivalent von Mises stress of the disc, as well as the contact pressure of the brake pads. Following the analysis of the results obtained, we drew several conclusions from this investigation. The choice allowed us to deliver the rotor design excellence to ensure and guarantee the good braking performance of the vehicles.

A predictive tool to evaluate braking system performance using a fully coupled thermo-mechanical finite element model

The braking phenomenon is an aspect of vehicle stopping performance where with kinetic energy due to speed of the vehicle is transformed to thermal energy via the friction between the brake disc and its pads. The heat must then be dissipated into the surrounding structure and into airflow around the brake system. The frictional thermal field during the braking phase between the disc and the brake pads can lead to excessive temperatures. In our work, we presented a numerical modeling using ANSYS software adapted in the finite element method, to follow the evolution of the global temperatures for the two types of brake discs, full and ventilated disc during braking scenario. Also, numerical simulation of the transient thermal and the static structural analysis were performed here sequentially, with coupled thermo-structural method. Numerical procedure of calculation relies on important steps such that the Computational Fluid Dynamics (CFD) and thermal analysis have been well illustrated in 3D, showing the effects of heat distribution over the brake disc. This CFD approach helped in the calculation of the values of the thermal coefficients (h) that have been exploited in the 3D transient evolution of the brake disc temperatures. Three different brake disc materials were tested and comparative analysis of the results was conducted in order, to derive the one with the best thermal behavior. Finally, the resolution of the coupled thermomechanical model allows us to visualize other important results of this research such as; the deformations, and the equivalent stresses of Von Mises of the disc, as well as the contact pressure of the brake pads. Following our analysis and results we draw from it, we derive several conclusions. The choice allowed us to deliver the rotor design excellence to ensure and guarantee the good braking performance of the vehicles.

A thermomechanical model for the analysis of disc brake using the finite element method in frictional contact

In this work, a numerical simulation of the transient thermal analysis and the static structural one was performed here sequentially, with the coupled thermo-structural method using the ANSYS software. Numerical procedure of calculation relies on important steps such that the CFD thermal analysis has been well illustrated in 3D, showing the effects of heat distribution over the brake disc. This CFD analysis helped in the calculation of the values of the thermal coefficients (h) that have been exploited in the 3D transient evolution of the brake disc temperatures. Three different brake disc materials were selected in this simulation and comparative analysis of the results was conducted in order, to derive the one with the best thermal behavior. Finally, the resolution of the coupled thermomechanical model allows to visualize other important results of this research such as; the deformations, and the equivalent stresses of Von Mises of the disc, as well as the contact pressure of the brake pads. Following our analysis and results we draw from it, we derive several conclusions. The choice makes it possible to deliver the best brake rotor so as to ensure and guarantee the good braking performance of the vehicles.

Finite element modeling of thermomechanical problems under the vehicle braking process

The braking phenomenon is an aspect of vehicle stopping performance where in kinetic energy due to speed of the vehicle is transformed into thermal energy produced by the brake disc and its pads. The heat must then be dissipated into the surrounding structure and into air flow around the brake system. The thermal friction field during the braking phase between the disc and the brake pads can lead to excessive temperatures. In our work, we presented numerical modeling using ANSYS software adapted in the finite element method, to follow the evolution of the global temperatures for the two types of brake discs, full and ventilated discs, during braking scenario. Also, numerical simulation of the transient thermal analysis and the static structural were performed here sequentially, with coupled thermo-structural method. Numerical procedure of calculation relies on important steps such that the Computational Fluid Dynamics (CFD) and thermal analysis have been well illustrated in 3D, showing the effects of heat distribution over the brake disc. This CFD analysis helped us in the calculation of the values of the thermal coefficients (h) that have been exploited in 3D transient evolution of the brake disc temperatures. Three different brake disc materials were tested and comparative analysis of the results was conducted in order, to derive the one with the best thermal behavior. Finally, the resolution of the coupled thermomechanical model allows us to visualize other important results of this research such as the deformations and the equivalent stresses of von Mises of the disc, as well as the contact pressure of the brake pads. Following our analysis and results we draw from it, we derive several conclusions. The choice allowed us to deliver the rotor design excellence to ensure and guarantee the good braking performance of the vehicles.

On-road vehicle measurements of brake wear particle emissions

Brake wear emissions are investigated during on-road driving with a midsize passenger car on a closed test track. A novel sampling system is designed that aims at monitoring the entire aspiration of brake wear particles. The wear particles are collected by a cone-shaped sampler, which is attached at the outer side of the wheel rim. Thus, the air flow direction penetrating the brake assembly from the vehicle underbody to the vehicle outside is preserved. For analysis, the wear aerosol is routed to the trunk of the car. In addition to the emission measurements, the setup flow is monitored, which enables quantification of the acquired emission data. A 3 h subsection of the Los Angeles City Traffic (LACT) cycle, representative for realistic driving behavior, is used as test cycle. For two different brake materials, PM10 emission factors are ranging from 1.4 mg km−1 brake−1 to 2.1 mg km−1 brake−1, while one material is found to be 18% less emissive. Due to high brake disc temperatures exceeding 170 °C, high particle number emissions occur through ultrafine particle generation. The unrealistic temperatures are caused by the limited brake cooling in the semi-closed measurement setup. In contrast, the reference brake temperature does not exceed 153 °C during the same test, thus ultrafine brake particle emissions are not expected during normal driving. Furthermore, well run-in brake material shows emission factors near the lower measurement limit at the unrealistic temperatures, suggesting that ultrafine particle emissions are characteristic for brand-new materials in combination with high brake temperatures observed due to the semi-closed housing of the measurement setup.

FEA Analysis of coupled thermo-mechanical response of grey cast iron material used in brake discs

In this work, we will present numerical modeling using the ANSYS software adapted for finite element method, to follow the evolution of the global temperatures for the two types of brake discs, full and ventilated disc during a braking scenario. Also, the numerical simulation of the transient thermal analysis and the static structural one is performed here sequentially with the coupled thermo-structural method. A numerical procedure of calculation relies on important steps such that the CFD thermal analysis is well illustrated in 3D, showing the effects of heat distribution over the brake disc. This CFD analysis will help us in the calculation of the values of the thermal coefficients (h) that will be exploited in the 3D transient evolution of the brake disc temperatures. Three different brake disc materials were selected in this simulation and a comparative analysis of the results was conducted in order to derive the one with the best thermal behavior. Finally, the resolution of the coupled thermomechanical model allows us to visualize other important results of this research such as; the deformations, and the equivalent stresses of Von Mises of the disc, as well as the contact pressure of the brake pads. Following our analysis and the results we draw from it, we derive several conclusions. The choice will allow us to deliver the best suitable design of the brake rotor to ensure and guarantee the good braking performance of vehicles.

Effect of heat transfer optimization on brake noise characteristics of automotive disc brake

Heat effect is one of the most important factors affecting the brake noise level. The finite element model for transient heat transfer analysis of disc brake is established based on heat transfer control equation and heat dissipation boundary conditions of dynamic convection. According to the NVH test and modal calculation, the brake noise characteristics are tested and analyzed. Meanwhile, the heat transfer simulation is verified and shows high accuracy. The discrete data for the response surface function are obtained by the Central Composite Design method with the peak temperature and mass as the target variables. The error of regression function is judged by fitting decision coefficient, correcting decision coefficient and root mean square error. By the optimizing mathematical model, the brake disc temperature peak can be greatly reduced and the heat transfer ability is obviously optimized without mass increasing, the time with temperature above 120 °C can be reduced by 46 %. Through the comparison of brake noise level before and after optimization, it can be known that the noise level can be significantly decreased after structural optimization, except the first order resonance frequency. The optimization result has good social and economic value.

A novel real-world braking cycle for studying brake wear particle emissions

Until now, a wide range of braking conditions has been applied in non‐exhaust emissions related studies. This often led to incomparable results and contradictory conclusions. Furthermore, there is no industry-wide accepted brake cycle available that represents real-world braking conditions.In this study a novel braking cycle is presented aiming towards a commonly accepted methodology for sampling and measuring brake wear particles. The cycle is based on the WLTP reference database, which includes in-use driving data from five different world regions with a total mileage of 740,000 km. The cycle development and statistical match to the WLTP database is presented. Experimental testing of the cycle both on the brake dynamometer and vehicle level are shown. Brake disc temperature behaviour on the real vehicle and dynamometer level is compared. It is shown that below a disc temperature of 160 °C, particle number emission is at background and sharply increases at brake temperatures above.

Development of remote data acquisition system based on OPC for brake test bench

The 1:1 train brake system test bench can be used to carry out brake-related adhesion-slid control, stability test, noise test and dynamic test. To collect data of the test bench, a data acquisition method is needed. In this paper, the remote data acquisition system of test bench is built by LabVIEW based on OPC technology. Unlike the traditional hardwire way connecting PLC acquisition module with sensors, the novel method is used to collect data and share them through the internal LAN built by Ethernet switches, which avoids the complex wiring interference in an easy, efficient and flexible way. The system has been successfully applied to the data acquisition activities of the comprehensive brake system test bench of CRRC Nanjing Puzhen Haitai Brake Equipment Co., Ltd., and the relationship test between the adhesion coefficient and the slip-ratio is realized. The speed signal, torque signal and brake disc temperature can be collected and displayed. The results show that the system is reliable, convenient, and efficient, and can meet the requirements of data acquisition.

Study on Braking Sensation Based on Urban Working Conditions

In this paper we researched the vehicle braking sense in three aspects of human, vehicle and environment and analysed their impacts on brake feeling. Through the real vehicle test we analysed the relationship among pedal force, pedal travel and deceleration. We used dynamometer test method to study the brake noise question. We designed a fixture which could imitate the suspension and made the test more close to the true level. Moreover we discussed how to establish the evaluation system of vehicle braking condition. Through real vehicle test of braking, we can test and record the brake system parameters in the braking process under urban working conditions. We recorded the brake frequency, the change of brake speed and brake disc temperature. Meanwhile, based on the analysis of braking condition, we put forward the index of brake load to reflect the city’s traffic conditions. Experiment show that the braking condition and brake feel are related, braking condition also provides theoretical support for the design of brake system.

Transient thermal response of a highly porous ventilated brake disc

The transient thermal response of a newly developed ventilated brake disc cored with a porous medium (wire-woven bulk diamond) is compared with those of a solid brake disc and a conventionally ventilated brake disc with pin fins. The best-performing brake disc vis-à-vis the operating temperature is dependent on the duration of braking: for a short braking event, T(solid) < T(pin-finned) < T(porous); however, for extended braking T(porous) < T(pin-finned) < T(solid). These experimental results are explained in terms of the governing thermophysical parameters using a classical first-order unsteady-state differential equation. The initial rate of increase in the brake disc temperature is dominated by the thermal capacity term; hence, for a short braking event, solid discs with a large thermal capacity operate at a low temperature. However, for extended braking, ventilated discs run cooler and reach lower steady-state temperatures than solid rotors do owing to the increased convective surface area and the forced convection in the ventilated channels. With the wire-woven bulk diamond core which allows a slightly lighter disc than the conventional pin-finned disc, a substantially lower steady-state temperature can be achieved, resulting from promoted flow mixing by three-dimensional wire-woven bulk diamond ligaments which enhance convection.

Experimental and Simulation Research on Relationships of the Pattern of a Friction Pair and Temperature

The pattern of a friction pair is an important factor affecting the friction braking temperature. Focusing on three different patterns of friction pairs formed with round,triangle and hexagon pad,braking experiments are conducted on an inertia test bench under the conditions of 50-250 km/h initial velocities. Using ABAQUS software simulation three kinds of the friction brake disc temperature field are conducted under different conditions. The results indicate that the numerical simulation of the temperature field matches the experimental results well. The influence of the friction pair structure on the disc surface temperature distribution is closely related to the braking conditions and is most obvious at the beginning of braking,and increase with the increase of braking initial velocity and braking pressure. This is because different structures of the friction pair lead to different distributions of the arc length. Friction arc length differences in turn amplifies the energy difference with the increase of the braking speed and high pressure,resulting in increased sensitivity of the brake disc temperature distribution to the brake pad structure.

Secondary Developments of ANSYS for Temperature and Stress Field Simulation of Brake Disc Based on VB

In the ANSYS finite element analysis with large-sized computer there is always a need for repeatedly modeling some similar questions. By using both the ANSYS for a secondary development platform and visual basic 6.0 for a visual operation interface, an APDL language is generated, so that a parametric modeling can be realized. With the help of the created software, the temperature and stress field contours of brake disc can be calculated and the efficiency of the calculation is enhanced.

The Thermo-Mechanical Coupling Analysis of Disc Brakes Transient Temperature Field

With the higher speed of the car, brake disc temperature will increase sharply when emergency braking, and its performance is demanded more and more higher. According to the Heat Conduction Theory, a brake disc's Thermo-mechanical Coupling model is built using ABAQUS software to analyze the brake disc transient temperature field. The analysis results shows that there is temperature gradient along the radial direction and axial direction, the temperature of the surface nodes with braking time has a wavy change, and the simulation result can be used as the references of brake disc design and selection.

Impact of Brake Pad Structure on Temperature and Stress Fields of Brake Disc

Utilizing ABAQUS finite element software, the study established the relationship between a brake pad structure and distributions of temperature and thermal stress on brake disc. By introducing radial structure factor and circular structure factor concepts, the research characterized the effect of friction block radial and circumferential arrangement on temperature field of the brake disc. A method was proposed for improving heat flow distribution of the brake disc through optimizing the position of the friction block of the brake pad. Structure optimization was conducted on brake pads composed of 5 or 7 circular friction blocks. The result shows that, with the same overall contact area of friction pair, an appropriate brake pad structure can make the friction energy distribute evenly and therefore lowers peak temperature and stress of the brake disc. Compared with a brake pad of 7 friction blocks, an optimized brake pad of 5 friction blocks lowered the peak temperature of the corresponding brake disc by 4.9% and reduced the highest stress by 10.7%.

Prediction of the cooling factors of a vehicle brake disc and its influence on the results of a thermal numerical simulation

In the process of developing the brake disc, it is necessary that we predict the suitability of the design. In this manner, we can affirm that even the first prototype will satisfy all of the customer homologation requests. Usually those comprise different sequential braking tests in which the maximal achieved temperature is the criterion that governs brake disc suitability. The knowledge of how to predict the behavior of a brake disc in the early pretesting phase has a significant impact on development costs and time. The common method that is used for predicting the temperatures in the brake disc during braking is numerical simulation analysis. With the help of Computational Fluid Dynamics, the flow through a vehicle ventilated brake disc of known geometry was determined, and the wall heat transfer coefficients for all vehicle speeds and brake disc temperatures were calculated. The results were then imported into a thermal numerical simulation of a sequential-braking vehicle test. The results showed that the consideration of cooling factors has a significant impact on temperature courses. To obtain accurate results from the numerical simulation and to simulate the vehicle test precisely, the proper wall heat transfer coefficients must be considered. The proposed method produces more accurate numerical results and enables the development engineer to develop suitable brake disc geometry in the early pretesting phase.

Monitoring of temperature and emissivity during successive disc revolutions in braking

The main difficulties of brake disc infrared temperature measurements are the unknown of disc surface emissivity, non-uniform and time-varying, and the high rotation speed and deceleration of the disc, which makes it difficult to follow the special distribution of the temperature. To provide information on the emissivity variation during braking, brake disc temperature and emissivity were investigated by an original optic-fiber two-color pyrometer combined with an infrared camera, which allows monitoring the true friction areas. In addition, an optical top-tour was used to identify disc revolutions. The evolutions of the surface temperature and emissivity on successive disc revolutions were successfully determined. It was showed that circumferential thermal gradients form on the surface and maintain their angular position, they can, however, win or lose in intensity with braking progress.