Exploration of Enhanced Heat Dissipation Design for Brake Disc of High Speed Train

2010 ◽  
Author(s):  
Zhizhuang Yu ◽  
Yong Wang
Keyword(s):  
Thermal Load ◽  
High Speed ◽  
Gas Flow ◽  
Heat Dissipation ◽  
Brake Disc ◽  
Frictional Surface ◽  
Brake Shoe ◽  
Remarkable Effect ◽  
Gas Channel ◽  
Heat Transfer Theory

The function of the brake disc is to provide the ultimate guarantee of the safety of high speed trains. A braking unit includes two discs and two brake shoes. Braking performance depends on the pressure of the brake shoe and the friction between the disc and the shoe. When a train is braked, the brake disc endures a thermal load, which may affect the mechanical properties of the disc. If the thermal load exceeds the strength limit of the material, it could impact the safe running of the train. Therefore, the thermal load should be reduced as much as possible. Now the frictional surface of disc is plane and heat congregates easily in the surface area. The purpose of this paper is to explore a design for enhanced heat dissipation. A gas channel was used on the frictional surface to achieve the effect of heat dissipation. This design was analyzed by means of tribology and heat transfer theory. The distribution of gas flow was also researched. The temperature and stress field of the disc were simulated and analyzed. By the analysis it can be seen that the gas channel on the frictional surface of disc has a remarkable effect on heat dissipation in the brake disc.

Numerical Simulation of the Cold Spray Deposition Process for Aluminium and Copper

2012 ◽  
Author(s):  
Jing Xie ◽  
Daniel Nelias ◽  
Hélène Walter-le Berre ◽  
Yuji Ichikawa ◽  
Kazuhiro Ogawa
Keyword(s):  
Reference Frame ◽  
Cold Spray ◽  
High Speed ◽  
Gas Flow ◽  
Heat Dissipation ◽  
Spray Deposition ◽  
Deposition Process ◽  
Arbitrary Lagrangian Eulerian ◽  
Systematic Analysis ◽  
The Impact

Cold spray is a rapidly developing coating technology for depositing materials in the solid state. In this deposition process, the spray particles are accelerated to a high velocity by a high-speed gas flow, and then form a dense and high quality coating due to plastic deformation of particles impinged upon the solid surface of substrate. 2D and 3D modelling of particle impacting behaviours in cold spray deposition process by using ABAQUS/Explicit was conducted for four couples of materials (i.e. impacting particle/impacted substrate): copper/aluminium, aluminium/copper, copper/copper, and aluminium/aluminium. A systematic analysis of a single impact was carried out considering different parameters, such as the initial impact velocity, initial temperature and contact angle, which affect the deposition process and subsequently the mechanical properties of coating. Three numerical methods have been evaluated and their performances are discussed for various simulation settings: (i) modelling in a Lagrangian reference frame; (ii) modelling using adaptive remeshing in an Arbitrary Lagrangian Eulerian (ALE) reference frame; and (iii), modelling in a CEL reference frame. It is found that the Coupled Eulerian Lagrangian (CEL) method has more advantages to simulate the large deformation of materials, and is also more efficient to prevent the excessive distortion of the mesh. A comparison between simulation results and experimental data from the literature was performed. Nevertheless, the CEL method is implicitly isothermal for ABAQUS v6.10, whereas the modelling in the classical Lagrangian reference frame does include coupled thermo-mechanical effects with a local increase of the temperature near the interface — due to friction — and for the highly plastically deformed elements — due to the heat dissipation linked to plasticity. A local rise of temperature at the impact surface may also be observed for oblique impacts. Finally a first attempt to simulate the deposition of several particles is made with a 3D CEL model, resulting in the creation of porosity at the interface between particles.

scholarly journals Design and analysis of disc brake system in high speed vehicles

2021 ◽  
Vol 12 ◽  
pp. 19
Author(s):  
Anil Babu Seelam ◽  
Nabil Ahmed Zakir Hussain ◽  
Sachidananda Hassan Krishanmurthy
Keyword(s):  
Stainless Steel ◽  
Cast Iron ◽  
High Speed ◽  
Heat Dissipation ◽  
Optimal Choice ◽  
Grey Cast Iron ◽  
Brake Disc ◽  
Disc Brake ◽  
Brake Rotor ◽  
Grey Cast

Brakes are the most important component of any automobile. Brakes provide the ability to reduce or bring automobile to a complete stop. The process of braking is usually achieved by applying pressure to the brake discs. The main objective of this research paper is to propose an appropriate design and to perform analysis of a suitable brake rotor to enhance the performance of the high-speed car. The design of the brake disc is modelled using Solid works and the analysis is carried out using Ansys software. The analysis has been conducted by considering stainless steel and grey cast iron using same brake rotor design so that optimal choice of brake disc can be considered. The analysis considered involves static structural analysis and steady state thermal analysis considering specific parameters on brake rotor to increase the life of brake rotor. From the analysis it is found that the performance and life of disc brake depends upon heat dissipation. From the analysis results it can be concluded that grey cast iron has performed better as compared to stainless steel as this material has anti-fade properties which improves the life of the brake rotor.

scholarly journals Temperature Field and Thermal Stress Analyses of High-Speed Train Brake Disc Under Pad Variations

2015 ◽  
Vol 9 (1) ◽  
pp. 371-378 ◽  
Author(s):  
Chen Jiguang ◽  
Gao Fei
Keyword(s):  
Heat Transfer ◽  
Temperature Field ◽  
Thermal Stress ◽  
High Speed ◽  
Heat Dissipation ◽  
Surface Radiation ◽  
Temperature Fields ◽  
Heat Transfer Analysis ◽  
Frictional Heat ◽  
Brake Disc

Transient heat transfer analysis of disc brake has been performed to find out an ideal shape of pad geometry. The analysis has taken frictional heat between brake disc and pads as heat flux onto the friction surface, the disc and the pad's temperature fields then were explored involving thermal conduction, forced convection and surface radiation effects. The disc thermal expansion stress was then acquired by quasi-static analysis using its temperature of aforesaid heat transfer analysis. Five prototypes of pad designs with geometry and volume variations were implemented for analytical comparison. Both pads and disc are required to have lower and uniform temperature field and thermal stress. The results uncover that heat conduction is domination in heat dissipation progress during braking, and big volume pad is cooler. Pad volume has more impact to heat transfer procedure and temperature gradient than pad geometry variation does. The design has 10 triangle pads is considered to be an ideal candidate. Its maximum disc temperature and thermal stress are the least among the five designs.

scholarly journals Tribo-Brake Characteristics between Brake Disc and Brake Shoe during Emergency Braking of Deep Coal Mine Hoist with the High Speed and Heavy Load

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5094
Author(s):  
Dagang Wang ◽  
Ruixin Wang ◽  
Tong Heng ◽  
Guozheng Xie ◽  
Dekun Zhang
Keyword(s):  
Coal Mine ◽  
High Speed ◽  
Brake Disc ◽  
Disc Brake ◽  
Heavy Load ◽  
Brake Shoe ◽  
Emergency Braking ◽  
Deep Coal Mine ◽  
Friction Disc ◽  
Mine Hoist

The friction wear and thermal fatigue cracking of the brake shoe and friction-induced self-excited vibration (frictional flutter) of the disc brake can easily occur during emergency braking of a deep coal mine hoist with at high speed and with a heavy load. Therefore, tribo-brake characteristics between the brake disc and brake shoe during emergency braking of a deep coal mine hoist are investigated in the present study. Scaled parameters of the disc brake of a deep coal mine hoist are determined by employing the similarity principle. Friction tests between friction disc and brake shoe are carried out to obtain the coefficient of friction in the case of high speed and large specific pressure between the friction disc and brake shoe. Coupled thermo-mechanical finite element analyses of the brake disc and brake shoe are established to investigate temperature and stress fields of the brake disc and brake shoe during emergency braking, which is validated by the engineering failure case. Effects of braking parameters on flutter characteristics between the brake disc and brake shoe are explored by employing a double-degrees-of-freedom vibration mechanism model. The results show that the maximum temperature, equivalent Von Mises stress and contact pressure are all located at the average friction radii of contact surfaces of the brake disc and brake shoe during emergency braking. The cage crashing accident in the case of high speed and heavy load in a typical coal mine shows crack marks and discontinuous burn marks at central locations of brake shoe and brake disc surfaces, respectively, which indicates frictional flutter characteristics between brake disc and brake shoe. During emergency braking, flutter time duration decreases with increasing initial braking speed and damping parameter; the flutter amplitude and frequency of the disc brake increases with increasing normal braking load and stiffness, respectively.

DESIGN AND THERMAL ANALYSIS OF BRAKE ROTOR WITH DIFFERENT MATERIALS

2020 ◽  
Vol 15 (2) ◽  
Author(s):  
Sugunarani S ◽  
Santhosh V
Keyword(s):  
Temperature Distribution ◽  
Heat Dissipation ◽  
Brake Disc ◽  
Element Analysis ◽  
Analysis Techniques ◽  
Engineering Software ◽  
The Finite Element Analysis ◽  
Brake Rotor ◽  
Grey Cast ◽  
Aluminium Metal

This work deals with the analysis of heat generation and dissipation in the disc brake of a car during braking and the following release period by using computer-aided engineering software for three different materials of the rotor disc and brake pad. The objective of this work is to analyze the temperature distribution of rotor disc during operation using COMSOL Multiphysics. The work uses the finite element analysis techniques to calculate and predict the temperature distribution on the brake disc and to identify the critical temperature of the brake rotor disc. Conduction, convection and radiation of heat transfer have been analyzed. The results obtained from the analysis indicates that different material on the same retardation of the car during braking shows different temperature distribution. A comparative study was made between grey cast iron (GCI), Aluminium Metal Matrix Composite (AMMC), Alloy steel materials are used for brake disc and the best material for making brake disc based on the rate of heat dissipation have been suggested.

Tribological and dynamical analysis of a brake pad with multiple blocks for a high-speed train

2019 ◽  
Vol 234 (11) ◽  
pp. 1771-1788
Author(s):  
YK Wu ◽  
JL Mo ◽  
B Tang ◽  
JW Xu ◽  
B Huang ◽  
...  
Keyword(s):  
High Speed ◽  
Wear Behavior ◽  
Dynamical Analysis ◽  
Brake Disc ◽  
Brake Pad ◽  
High Speed Train ◽  
Brake Squeal ◽  
Element Analysis ◽  
Single Block ◽  
Middle Ring

In this research, the tribological and dynamical characteristics of a brake pad with multiple blocks are investigated using experimental and numerical methods. A dynamometer with a multiblock brake pad configuration on a brake disc is developed and a series of drag-type tests are conducted to study the brake squeal and wear behavior of a high-speed train brake system. Finite element analysis is performed to derive physical explanations for the observed experimental phenomena. The experimental and numerical results show that the rotational speed and braking force have important influences on the brake squeal; the trends of the multiblock and single-block systems are different. In the multiblock brake pad, the different blocks exhibit significantly different magnitudes of contact stresses and vibration accelerations. The blocks located in the inner and outer rings have higher vibration acceleration amplitudes and stronger vibration energies than the blocks located in the middle ring.

scholarly journals Heat Transmission in High Speed Gas Flow (3rd Report)

1952 ◽  
Vol 18 (67) ◽  
pp. 31-35
Author(s):  
Kensuke KAWASHIMO ◽  
Shigebumi AOKI
Keyword(s):  
High Speed ◽  
Gas Flow ◽  
Heat Transmission

Numerical Modeling and Simulation Analysis of Temperature Field of Disc Brake on Trains

2011 ◽  
Vol 199-200 ◽  
pp. 1492-1495 ◽  
Author(s):  
Guo Shun Wang ◽  
Rong Fu ◽  
Liang Zhao
Keyword(s):  
Temperature Field ◽  
Temperature Gradient ◽  
High Speed ◽  
Large Scale ◽  
Working Condition ◽  
Constant Speed ◽  
Brake Disc ◽  
Disc Brake ◽  
Brake Pad ◽  
Finite Element Software

The simulation calculation on the temperature field of the disc brake system on high-speed trains under the working condition of constant speed at 50Km/h is made. A steady-state calculation model is established according to the actual geometric size of a brake disc and a brake pad, and the analog calculation and simulation on the temperature field of the brake disc and the brake pad by using the large-scale nonlinear finite element software ABAQUS are carried out. The distribution rules of the temperature field of the brake disc and the brake pad under the working condition of constant speed are made known. The surface temperature of the brake disc at friction radius is the highest, with a band distribution for temperature. There exists a temperature flex point in the direction of thickness, of which the thickness occupies 15% of that of the brake disc; due to the small volume of the brake pad, the temperature gradient of the whole brake pad is not sharp, and larger temperature gradient occurs only on the contact surface.

Experimental Inverstigations On the Pressure Fluctuations in the Sealing Gap of Dry Gas Seals with Embedded Pressure Sensors

2021 ◽  
Author(s):  
Jingjing Luo ◽  
Dieter Brillert
Keyword(s):  
High Speed ◽  
Gas Flow ◽  
Static Pressure ◽  
Pressure Sensors ◽  
Operating Conditions ◽  
Test Facility ◽  
Experimental Investigations ◽  
Mechanical Seals ◽  
Process Gas ◽  
Sealing Gap

Abstract Dry gas lubricated non-contacting mechanical seals (DGS), most commonly found in centrifugal compressors, prevent the process gas flow into the atmosphere. Especially when high speed is combined with high pressure, DGS is the preferred choice over other sealing alternatives. In order to investigate the flow field in the sealing gap and to facilitate the numerical prediction of the seal performance, a dedicated test facility is developed to carry out the measurement of key parameters in the gas film. Gas in the sealing film varies according to the seal inlet pressure, and the thickness of gas film depends on this fluctuated pressure. In this paper, the test facility, measurement methods and the first results of static pressure measurements in the sealing gap of the DGS obtained in the described test facility are presented. An industry DGS with three-dimensional grooves on the surface of the rotating ring, where experimental investigations take place, is used. The static pressure in the gas film is measured, up to 20 bar and 8,100 rpm, by several high frequency ultraminiature pressure transducers embedded into the stationary ring. The experimental results are discussed and compared with the numerical model programmed in MATLAB, the characteristic and magnitude of which have a good agreement with the numerical simulations. It suggests the feasibility of measuring pressure profiles of the standard industry DGS under pressurized dynamic operating conditions without altering the key components of the seal and thereby affecting the seal performance.

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