Thermal analysis of brake disc 2015

1
“In pursuit of Global Competitiveness”
A PROJECT ON
‘THERMAL ANALYSIS OF BRAKE DISC’
For the degree of Bachelor of Engineering (Mechanical)
2014-2015
Submitted By
Mr. PENGKAM KENGLANG LUNGCHANG(BE06F02F065)
Mr. PARAG DESHATTIWAR (BE10F02F068)
Mr. KAHANI MENJO (BE11F02F064)
Mr. TOSHIF RUIKAR (BE11F02F046)
Mr. SANJEET KUMAR (BE11F02F065)
In partial fulfilment of
Bachelor of Engineering
(Mechanical Engineering)
Under the guidance of
Dr. R.K SHRIVASTAVA
Department of Mechanical Engineering
Government College of Engineering, Aurangabad
(2014-2015)

2
CERTIFICATE
This is to certify that, the seminar “THERMAL ANALYSIS OF BRAKE DISC”
submitted by Penkam K. Lungchang, Parag Deshattiwar, Toshif Ruikar, Kahani Menjo,
Sanjeet Kumar is a bona fide work completed under my supervision and guidance in partial
fulfilment for award of Bachelor of Engineering (Mechanical) Degree of Government College of
Engineering (An Autonomous Institute of Government of Maharashtra) affiliated to Dr.
Babasaheb Ambedkar Marathwada University, Aurangabad, Maharashtra.
Place: Aurangabad
Date:
Dr. R. K. Shrivastava
Guide & Head of Department,
Department of Mechanical Engineering,
Govt. College of Engineering,
Aurangabad
Dr. P. S. Adwani
Principal,
Government College of Engineering,
Aurangabad

3
CONTENT
1. INTRODUCTION 1
2. LITERATURE REVIEW 2
3. BACKGROUND THEORY
3.1 BRAKING SYSTEM 4
3.2 HEAT TRANFERENCE 9
3.3 MATERIAL USED FOR BRAKE MANUFACTURING 10
3.4 MANUFACTURING PROCESS OF DISC BRAKE 12
4. FINITE ELEMENT METHOD
4.1 INTRODUCTION 15
4.2 GENERAL PROCEDURE 15
4.3 CONVERGENCE REQUIREMENT 17
4.4 ADVANTAGES OF FEM 18
4.5 LIMITATIONS OF FEM 18
4.6 APPLICATION OF FEM 18
5. FEA SOFWARE – ANSYS
5.1 INTRODUCTION 19
5.2 EVOLUTION OF FEA 20
5.3 OVERVIEW OF THE PROGRAM 20
5.4 REDUCING THE DESIGN & MANUFACTURING COST USING ANSYS 22
5.5 PROCEDURE FOR ANSYS ANALYSIS 23
5.6 BUILD THE MODEL 24
5.7 MATERIAL PROPERTIES 24
5.8 OBTAIN THE SOLUTION 24
6. DISC BRAKE CALCULATIONS
6.2 ASSUMPTION 28
6.2 CALCULATION FOR INPUT PARAMETER 28
6.3 ANALYTICAL TEMPERATURE RISE CALCULATIONS 30
7. FEM MODELS OF BRAKE DISC WITH MESHING 32
8. RESULT 35

4
9. DISCUSSION 41
10. CONCLUSION 42
APPENDIX A 43
APPENDIX B 44
APPENDIX C 45
APPENDIX D 46
APPENDIX E 47
APPENDIX F 48
APPENDIX G 49
APPENDIX H 50
APPENDIX I 51
REFERENCE 52
ACKNOWLEDGEMENT 53

5
LIST OF FIGURES
Fig.
no.
Description
Page
no.
1. DISK BRAKING SYSTEM OF TWO WHEELER 6
2.1 MATERIAL ANALYSIS 11
2.2 INCLINED ROW DRILLED DISC 12
2.3 CURVED ROW OF DRILLED DISC 12
2.4 CROSSED ROW OF DRILLED DISC 13
2.5 SLOT DISC 13
2.6 SLOT AND DRILLED DISC 13
2.7 INCLINED ROW OF SLOTTED DISC 14
2.8 MINIMUM LIGMENT LENGTH FOR VARIOUS PATTERN 14
5.1 SCHEMATIC DIAGRAM OF A DISC BRAKE
7.1 MESHING OF MODEL 1 31
8.1 TEMPERATURE DISTRIBUTION PLOT FOR SS MODEL NO. 1 34
8.2 HEAT FLUX PLOT SS MODEL NO. 1 34
8.3 TEMPERATURE DISTRIBUTION PLOT SS MODEL NO. 2 35
8.5 TEMPERATURE DISTRIBUTION PLOT SS MODEL NO. 3 36
8.7 TEMPERATURE DISTRIBUTION PLOT CI MODEL NO. 1 37
8.8 HEAT FLUX PLOT CI MODEL NO. 1 37

6
LIST OF TABLES
TABLE
NO.
DESCRIPTION PAGE
NO.
6.1 CALCULATION FOR INPUT PARAMETERS 30
6.2 MATERIAL PROPERTIES FOR STAINLESS STEEL AND CAST IRON 30
9.1 MAXIMUM AND MINIMUM TEMPERATURE DISTRIBUTION 40
9.2 MAXIMUM AND MINIMUM TOTAL HEAT FLUX 40

7
LIST OF ABBREVIATION
ABBREVIATION ILLUSTRATION
FE FINITE ELEMENT
ANSYS ANALYSIS SYSTEM
CATIA
COMPUTER AIDED THREE DIMENSIONAL INTERACTIVE
APPLICATION
HSS HIGH SPEED STEEL
SS STAINLESS STEEL
CI CAST IRON
M METER
W WATT
K KELVIN
Q HEAT FLUX
A SURFACE AREA
T TEMPERATURE
H ENTHALPY
FEA FINITE ELEMENT ANALYSIS
Ψ PSI
[K] STIFFNESS MATRIX
INC. INCORPORATED
U INITIAL VELOCITY
G ACCERLATION DUE TO GRAVITY
1-D ONE DIMENSIONAL
µ COEFFICIENT OF FRICTION

8
ABSTRACT
Braking is a process which converts the kinetic energy of the vehicle into mechanical
energy which must be dissipated in the form of heat. The disc brake is a device for de-
accelerating or stopping the rotation of a wheel. A brake disc (or rotor) usually made of cast iron
or ceramic composites, is connected to the wheel and/or the axle. Friction material in the form of
brake pads (mounted on a device called a brake calliper) is forced mechanically, hydraulically,
pneumatically or electromagnetically against both sides of the disc to stop the wheel. The present
research is basically deals with the modelling and analysis of solid and ventilated disc brake
using Pro-E and ANSYS. Finite element (FE) models of the brake-disc are created using Pro-E
and simulated using ANSYS which is based on the finite element method (FEM). In this research
Coupled Analysis (Structural & Thermal analysis) is performed in order to find the strength of
the disc brake. In structural analysis displacement, ultimate stress limit for the design is found
and in thermal analysis thermal gradients, heat flow rates, and heat fluxes to be calculates by
varying the different cross sections, materials of the disc. Comparison can be done for
displacement, stresses, nodal temperatures, etc. for the three materials to suggest the best
material for FSAE car.
The disc brake is a device used for slowing or stopping the rotation of the vehicle.
Number of times using the brake for vehicle leads to heat generation during braking event, such
that disc brake undergoes breakage due to high Temperature. Disc brake model is done by
CATIA/PROE and analysis is done by using ANSYS workbench. The main purpose of this
project is to study the Thermal analysis of the Materials for the Cast Iron, and HSS M2. A
comparison between the four materials for the Thermal values and material properties obtained
from the Thermal analysis low thermal gradient material is preferred. Hence best suitable design,
low thermal gradient material Grey cast iron is preferred for the Disc Brakes for better
performance.

9
1. INTRODUCTION
In today’s growing automotive market the competition for better performance vehicle is
growing enormously. The disc brake is a device used for slowing or stopping the rotation of the
wheel. A brake is usually made of cast iron or ceramic composites include carbon, aluminum,
Kevlar and silica which is connected to the wheel and axle, to stop the vehicle. A friction
material produced in the form of brake pads is forced mechanically, hydraulically, pneumatically
and electromagnetically against the both side of the disc. This friction causes the disc and
attached wheel to slow or to stop the vehicle. The methods used in the vehicle are regenerative
braking system and friction braking system. A friction brake generates the frictional force in two
or more surfaces rub against to each other, to reduce the movement. Based on the design
configurations vehicle friction brakes are grouped into disc brakes and drum brakes. Our project
is about disc brakes modeling and analysis.
Repetitive braking of a vehicle generates large amount of heat. This heat has to be
dissipated for better performance of brake. Braking performance largely affected by the
temperature rise in the brake components. High temperature may cause thermal cracks, brake
fade, wear and reduction in coefficient of friction.
During braking, the kinetic and potential energies of a moving vehicle get converted into
thermal energy through friction in the brakes. The heat generated between the brake pad & disc
has to be dissipated by passing air over them. This heat transfer takes place by conduction,
convection and somewhat by radiation. To achieve proper cooling of the disc and the pad by
convection, study of the heat transport phenomenon between disc, pad and the air medium is
necessary. Then it is important to analyze the thermal performance of the disc brake system to
predict the increase in temperature during braking. Convective heat transfer model has been
developed to analyze the cooling performance. Brake discs are provided with cuts to increase the
area coming in contact with air and improve heat transfer from disc.
In this paper two different cut patterns of brake disc are studied for heat transfer rate.
Heat transfer rate increases with number of cuts in the disc. This is because large area is exposed
to air which makes more heat transfer through conduction and convection. But increase in
number and size of cuts decreases the strength of disc.

10
2. LITERATURE REVIEW
Gao and Lin (2002) presented Transient temperature field analysis of a brake in a non-
axisymmetric three-dimensional model [1]. The disk-pad brake used in an automobile is divided
into two parts: the disk, geometrically axisymmetric; and the pad, of which the geometry is
three-dimensional. Using a two-dimensional model for thermal analysis implies that the contact
conditions and frictional heat flux transfer are independent of y. This may lead to false thermal
elastic distortions and unrealistic contact conditions. An analytical model is presented in this
paper for the determination of the contact temperature distribution on the working surface of a
brake. To consider the effects of the moving heat source (the pad) with relative sliding speed
variation, a transient finite element technique is used to characterize the temperature fields of the
solid rotor with appropriate thermal boundary conditions. Numerical results shows that the
operating characteristics of the brake exert an essentially influence on the surface temperature
distribution and the maximal contact temperature.
Voller, et al.(2003) perform an Analysis of automotive disc brake cooling characteristics
[2]. The aim of this investigation was to study automotive disc brake cooling characteristics
experimentally using a specially developed spin rig and Singh and Shergill 85 numerically using
finite element (FE) and computational fluid dynamics (CFD) methods. All three modes of heat
transfer (conduction, convection and radiation) have been analyzed along with the design
features of the brake assembly and their interfaces. The influence of brake cooling parameters on
the disc temperature has been investigated by FE modelling of a long drag brake application. The
thermal power dissipated during the drag brake application has been analyzed to reveal the
contribution of each mode of heat transfer.
Choi and Lee, (2004) presented a paper on Finite element analysis of transient
thermoelastic behaviors in disk brakes [3]. A transient analysis for thermoelastic contact problem
of disk brakes with frictional heat generation is performed using the finite element method. To
analyze the thermoelastic phenomenon occurring in disk brakes, the coupled heat conduction and
elastic equations are solved with contact problems. The numerical simulation for the
thermoelastic behavior of disk brake is obtained in the repeated brake condition. The
computational results are presented for the distributions of pressure and temperature on each
friction surface between the contacting bodies.

11
Qi and Day (2007) discussed that using a designed experiment approach, the factors
affecting the interface temperature, including the number of braking applications, sliding speed,
braking load and type of friction material were studied [4]. It was found that the number of
braking applications had the strongest effect on the friction interface temperature. The real
contact area between the disc and pad, i.e. pad regions where the bulk of the kinetic energy is
dissipated via friction, had a significant effect on the braking interface temperature. For
understanding the effect of real contact area on local interface temperatures and friction
coefficient, finite element analysis (FEA) was conducted, and it was found that the maximum
temperature at the friction interface does not increase linearly with decreasing contact area ratio.
This finding is potentially significant in optimizing the design and formulation of friction
materials for stable friction and wear performance.
Eltoukhy and Asfour (2008) present a paper on Braking Process in Automobiles:
Investigation of the Thermoelastic Instability Phenomenon. In this chapter a case study regarding
a transient analysis of the thermoelastic contact problem for disk brakes with frictional heat
generation, performed using the finite element analysis (FEA) method is described in details.
The computational results are presented for the distribution of the temperature on the friction
surface between the contacting bodies (the disk and the pad) [5]. Also, the influence of the
material properties on the thermoelastic behavior, represented by the maximum temperature on
the contact surface is compared among different types of brake disk materials found in the
literature, such as grey cast iron (grey iron grade 250, high-carbon grade iron, titanium alloyed
grey iron, and compact graphite iron (CGI)), Aluminum metal matrix composites (AlMMC's),
namely Al2O3 Al-MMC and SiC Al-MMC (Ceramic brakes).
Zaid, et al. (2009) presented a paper on an investigation of disc brake rotor by Finite
element analysis. In this paper, the author has conducted a study on ventilated disc brake rotor of
normal passenger vehicle with full load of capacity [6]. The study is more likely concern of heat
and temperature distribution on disc brake rotor. In this study, finite element analysis approached
has been conducted in order to identify the temperature distributions and behaviors of disc brake
rotor in transient response. ABAQUS/CAE has been used as finite elements software to perform
the thermal analysis on transient response. Thus, this study provide better understanding on the
thermal characteristic of disc brake rotor and assist the automotive industry in developing
optimum and effective disc brake rotor.

12
3. BACKGROUND THEORY
3.1. Braking system
A brake is a device by means of which artificial frictional resistance is applied to moving
machine member, in order to stop the motion of a machine. In the process of performing this
function, the brakes absorb either kinetic energy of the moving member or the potential energy
given up by objects being lowered by hoists, elevators etc. The energy absorbed by brakes is
dissipated in the form of heat. This heat is dissipated in to the surrounding atmosphere to stop the
vehicle, so the brake system should have the following requirements:
i. The brakes must be strong enough to stop the vehicle with in a minimum Distance in an
emergency.
ii. The driver must have proper control over the vehicle during braking and the vehicle must
not skid.
iii. The brakes must have good ant fade characteristics i.e. their effectiveness should not
decrease with constant prolonged application
iv. The brakes should have good anti-wear properties.
Based on mode of operation brakes are classified as follows:
1. Hydraulic brakes.
2. Electric brakes.
3. Mechanical brakes.
The mechanical brakes according to the direction of acting force may be sub divided into
the following two groups:
i. Radial brakes:
In these brakes the force acting on the brake drum is in radial direction. The radial brake
may be subdivided into external brakes and internal brakes.
ii. Axial brakes:
In these brakes the force acting on the brake drum is only in the axial direction. E.g. Disc
brakes, Cone brakes.

13
3.1.1 Disc brakes:
A disc brake consists of a cast iron disc bolted to the wheel hub and a stationary housing
called caliper. The caliper is connected to some stationary part of the vehicle, like the axle casing
or the stub axle and is cast in two parts, each part containing a piston. In between each piston and
the disc, there is a friction pad held in position by retaining pins, spring plates etc. passages are
drilled in the caliper for the fluid to enter or leave each housing.
These passages are also connected to another one for bleeding. Each cylinder contains
rubber-sealing ring between the cylinder and piston. A schematic diagram is shown in the figure
(1).
. The disc brake is a wheel brake which slows rotation of the wheel by the friction caused
by pushing brake pads against a brake disc with a set of calipers. The brake disc (or rotor in
American English) is usually made of cast iron, but may in some cases be made of composites
such as reinforced carbon–carbon or ceramic matrix composites. This is connected to the wheel
and/or the axle. To stop the wheel, friction material in the form of brake pads, mounted on a
device called a brake caliper, is forced mechanically, hydraulically, pneumatically or
electromagnetically against both sides of the disc. Friction causes the disc and attached wheel to
slow or stop. Brakes convert motion to heat, and if the brakes get too hot, they become less
effective, a phenomenon known as brake fade. Disc-style brakes development and use began in
England in the 1890s. The first caliper-type automobile disc brake was patented by Frederick
William Lanchester in his Birmingham, UK factory in 1902 and used successfully on Lanchester
cars. Compared to drum brakes, disc brakes offer better stopping performance, because the disc
is more readily cooled. As a consequence discs are less prone to the “brake fade”; and disc
brakes recover more quickly from immersion (wet brakes are less effective). Most drum brake
designs have at least one leading shoe, which gives a servo effect. By contrast, a disc brake has
no self-servo effect and its braking force is always proportional to the pressure placed on the
brake pad by the braking system via any brake servo, braking pedal or lever, this tends to give
the driver better “feel” to avoid impending lockup. Drums are also prone to “bell mouthing”, and
trap worn lining material within the assembly, both causes of various braking problems.

14
Figure (1) Disk Braking System of Two Wheeler
3.1.2 Break Pads
Brake pads convert the kinetic energy of the car to thermal energy by friction. Two brake
pads are contained in the brake caliper with their friction surfaces facing the rotor. When the
brakes are hydraulically applied, the caliper clamps or squeezes the two pads together into the
spinning rotor to slow/stop the vehicle. When a brake pad is heated by contact with a rotor, it
transfers small amounts of friction material to the disc, turning it dull gray. The brake pad and
disc (both now with friction material), then "stick" to each other, providing the friction that stops
the vehicle.
In disc brake applications, there are usually two brake pads per disc rotor, held in place
and actuated by a caliper affixed to a wheel hub or suspension upright. Although almost all road-
going vehicles have only two brake pads per caliper, racing calipers utilize up to six pads, with
varying frictional properties in a staggered pattern for optimum performance. Depending on the
properties of the material, disc wear rates may vary. The brake pads must usually be replaced
regularly (depending on pad material), and most are equipped with a method of alerting the
driver when this needs to take place. Some are manufactured with a small central groove whose
eventual disappearance through wear indicates that the pad is nearing the end of its service life.
Others are made with a thin strip of soft metal in a similar position that when exposed through

15
wear causes the brakes to squeal audibly. Still others have a soft metal tab embedded in the pad
material that closes an electric circuit and lights a dashboard warning light when the brake pad
gets thin.
The different types of brake pads that are most commonly used can be found below.
1.Metallic pads – metallic pads are undoubtedly the most common variety of brake pads and are
found on many of today’s vehicles. A unique blend of different metals creates metallic brake
pads and they’re affordable, durable and offer good performance. They’re best installed on
small vehicles that don’t witness very aggressive driving.
2.Organic pads – organic pads are made up of organic materials like rubber, glass and resin
which as the binding agent. Asbestos was the material of choice in earlier years as it dissipated
heat well. However, the dust created was dangerous to health and the environment so it was
replaced by more natural materials. Unlike metallic pads, organic pads are lightweight and
produce very little noise. They’re ideal for small vehicles and vehicles that don’t see a lot of
aggressive driving. However, their softness means they wear out faster so more dust is
produced.
3.Ceramic pads – ceramic brake pads are recommended for high performance vehicles that
witness sharp turns, high speeds and frequent stops. Ceramic pads are the most expensive of
the brake pads that are available as a consequence of its high performance and this means that
they are usually found on performance or racing cars as their distinctive advantages are best
suited to these performance models.
3.3.1 Material used in brake pad
The five most important characteristics that are considered when selecting a break pad
material are as follows:
a) The materials ability to resist brake fade at increased temperatures
b) The effects of water on brake fade (all brakes are designed to withstand at least temporary
exposure to water)
c) The ability to recover quickly from either increased temperature or moisture
d) Service life as traded off vs. wear to the rotor

16
e) The ability of the material to provide smooth, even contact with the rotor or drum (rather than
a material that breaks off in chunks or causes pits or dents)
Today, brake pad materials are classified as belonging to one of four principal categories,
as follows
a) Non-metallic materials - these are made from a combination of various synthetic substances
bonded into a composite, principally in the form of cellulose, aramid, PAN, and sintered glass.
They are gentle on rotors, but produce a fair amount of dust and have a short service life.
b) Semi-metallic materials - synthetics mixed with some proportion of flaked metals. These are
harder than non-metallic pads, and are more fade-resistant and longer lasting, but at the cost of
increased wear to the rotor/ drum which then must be replaced sooner. They also require more
force than non-metallic pads in order to generate braking torque.
c) Fully metallic materials - these pads are used only in racing vehicles, and are composed of
sintered steel without any synthetic additives. They are very long-lasting, but require even
more force to slow a vehicle and are extremely wearing on rotors. They also tend to be very
loud.
d) Ceramic materials - Composed of clay and porcelain bonded to copper flakes and filaments,
these are a good compromise between the durability of the metal pads and the grip and fade
resistance of the synthetic variety. Their principal drawback, however, is that unlike the
previous three types and despite the presence of the copper (which has a high thermal
conductivity), ceramic pads generally do not dissipate heat well, which can eventually cause
the pads or other components of the braking system to warp. However, because the ceramic
materials causes the braking sound to be elevated beyond that of human hearing, they are
exceptionally quiet.

17
3.2. Heat transference:
When a system is at a different temperature than its surroundings, the Nature tries to
reach thermal equilibrium. To do so, as the second law of thermodynamics explains, the thermal
energy always moves from the system of higher temperature to the system of lower temperature.
This transfer of thermal energy occurs due to one or a combination of the three basic heat
transport mechanisms: Conduction, Convection and Radiation.
3.2.1. Conduction:
Is the transference of heat through direct molecular communication, i.e. by physical contact
of the particles within a medium or between mediums. It takes place in gases, liquids and solids.
In conduction, there is no flow of any of the material mediums.
The governing equation for conduction is called the Fourier’s law of heat conduction and it
express that the heat flow per unit area is proportional to the normal temperature gradient, where
the proportionality constant is the thermal conductivity:
Where q is the heat flux perpendicular to a surface of area A, [W]; A is the surface area through
which the heat flow occurs, [m2] ; k is the thermal conductivity, [W/(mK)]; T is the temperature,
[K] or [°C]; and x is the perpendicular distance to the surface traveled by the heat flux.
3.2.2. Convection :
Convection is the heat transfer by mass motion of a fluid, when the heated fluid moves
away from the heat source. It combines conduction with the effect of a current of fluid that
moves its heated particles to cooler areas and replace them by cooler ones. The flow can be
either due to buoyancy forces (natural convection) or due to artificially induced currents (forced
convection).
The equation that represents convection comes from the Newton’s law of cooling and is of the
form:

18
Where h is the convective heat transfer coefficient [W/ (m2K)]; T∞ is the temperature of the
cooling fluid; and Ts is the temperature of the surface of the body.
3.2.3. Radiation :
In general, radiation is energy in the form of waves or moving subatomic particles.
Among the radiation types, we are specifically interested in the Thermal radiation. Thermal
radiation is heat transfer by the emission of electromagnetic waves from the surface of an object
due to temperature differences which carry energy away from the emitting object.
The basic relationship governing radiation from hot objects is called the Stefan-Boltzmann law:
Where ε is the coefficient of emissivity (=1 for ideal radiator); σ is the Stefan-Boltzmann
constant of proportionality (5.669E-8 [W/(m2K4)]); A is the radiating surface area; T1 is the
temperature of the radiator; and T2 is the temperature of the surroundings.
3.3. Material used for disc brake manufacturing
Properties to be considered
1. Coefficient of friction.
2. Wear rate.
3. Heat resistance.
4. Withstanding pressure.
5. Heat dissipation.
6. Thermal expansion.
7. Mechanical strength.
8. Moisture.
There have been two principal materials used for their production in recent years. Cast
Iron and Stainless Steel.

19
3.3.1 Cast Iron:
Cast iron is very cheap to produce and produces very good friction coefficients but it is also
fragile, it is not compatible with many modern pad materials, particularly sintered pads, it is
heavy and of course it rusts. Grey cast iron discs can shatter and ductile cast iron is fragile, very
fickle with pads and in our experience can warp very easily. We distributed a range of discs
made from ductile cast iron for several years and had to return far too many that were warped.
The answer usually came back that the problem had occurred due to the use of inappropriate
pads but the truth is it happened far too often! Some companies still believe it is the right
material to use but there are just too many negatives and not enough positives.
3.3.2 Stainless Steel:
Stainless steel on the other hand, although a little more expensive has a lot more
positives. It doesn’t rust, or at least not to any great extent. It is very robust, it is tolerant to
almost all brake pads and particularly to sintered brake pads. It is highly resistant to wear, it
doesn’t shatter and it resists heat very well. When it was first used the friction coefficients were
not as good as cast iron and this convinces some that cast iron is still the right material. But I
asked a Brembo executive about it some years ago and he said, that was true 30 years ago but the
friction coefficients of stainless steel discs and sintered pads went past cast iron around 20 years
ago! As usual, for proof he pointed to the race results and pointed out that with the exception of
carbon discs in GP, every race bike fitted with Brembo brakes for the last 20 years or so had
used stainless steel discs not cast iron. Since they are the winning brakes in almost every major
championship year in year out it is difficult to argue. The exact specification they use has never
been released but it is made especially for them.
Graph 2.1: Material analysis

20
3.4. Manufacturing process of disc brake
In modern days, the use of metal is vast and there are various methods of manufacturing a
product from only use of pure molten metal or from any other state of metal as well. When
considering the different methods of manufacturing, most popular methods used in large
industries are as follows:
i. Metal Casting
ii. Metal Cutting
iii. Metal Forming and shaping
iv. Fabrication and welding
The above mentioned are few that are used by industries to produce different products
that could make up a machine such as a vehicle, electronic components or other day to day
tools.
3.4.1. Different brake disc designs
Figure2.2: Inclined row drilled disc
Figure 2.3: Curved row of drilled disc

21
Figure2.4: Crossed row of drilled disc
Figure2.5: Slot disc
Figure2.6: Slot and drilled disc

22
Figure2.7: Inclined row of slotted disc
Figure 2.8: Minimum ligment length for various pattern

23
4. FINITE ELEMENT METHOD
4.1 Introduction to finite element method:
The finite element method is a powerful tool to obtain the numerical solution of wide
range of engineering problem. The method is general enough to handle any complex shape or
geometry, for any material under different boundary and loading conditions. The generality of
the finite element method fits the analysis requirement of today’s complex engineering systems
and designs where closed form solutions of governing equilibrium equations are usually not
available. In addition, it is an efficient design tool by which designers can perform parametric
design studies by considering various design cases, (different shapes, materials, loads, etc.) and
analyze them to choose the optimum design.
The method originated in the aerospace industry as a tool to study stress in a complex
airframe structures. It grows out of what was called the matrix analysis method used in aircraft
design. The method has gained increased popularity among both researchers and practitioners.
The basic concept of finite element method is that a body or structure may be divided into small
elements of finite dimensions called “finite elements”. The original body or the structure is then
considered, as an assemblage of these elements connected at a finite number of joints called
nodes or nodal points.
4.2.General procedure of finite element method:
The finite element method is a method of piecewise approximation in which the
structure or body is divided into small elements of finite dimensions called finite elements and
then the original body or the structure is considered as an assemblage of these elements
connected at finite number of joints called nodal points or nodes. Since the actual variation of
field variables like displacement, stress, temperature, pressure or velocity inside the continuum
are not known, the variation of the field variable inside a finite element can be approximated by a
simple function. These approximation functions called interpolation models are defined in terms
of the values of the field variables of the nodes. The nodal values of the field variable are
obtained by solving the field equations, which are generally in the form of matrix equations.

24
Once the nodal values are known, the approximating functions define the field variable
throughout the assemblage of elements.
The solutions of general continuum problems by the finite element method always follow
an orderly step-by-step process.
The step-by-step procedure for static structural problem can be stated as follows:
Step 1:- Description of Structure (Domain). The first step in the finite element method is to
divide the structure of solution region in to sub divisions or elements.
Step 2:- Selection of proper interpolation model. Since the displacement (field variable) solution
of a complex structure under any specified load conditions cannot be predicted exactly, we
assume some suitable solution, within an element to approximate the unknown solution. The
assumed solution must be simple and it should satisfy certain convergence requirements.
Step 3:- Derivation of element stiffness matrices (characteristic matrices) and load vectors. From
the assumed displacement model the stiffness matrix [K(e)] and the load vector P(e) of element
‘e’ are to be derived by using either equilibrium conditions or a suitable Variation principle.
Step 4:- Assemblage of element equations to obtain the equilibrium equations.
Since the structure is composed of several finite elements, the individual element
stiffness matrices and load vectors are to be assembled in a suitable manner and the overall
equilibrium equation has to be formulated as
[K]φ = P
Where [K] is called assembled stiffness matrix, Φ is called the vector of nodal
displacement and P is the vector or nodal force for the complete structure.
Step 5:- Solution of system equation to find nodal values of displacement (field variable). The
overall equilibrium equations have to be modified to account for the boundary conditions of the
problem. After the incorporation of the boundary conditions, the equilibrium equations can be
expressed as,
[K]φ = P

25
For linear problems, the vector ‘φ’ can be solved very easily. But for non-linear
problems, the solution has to be obtained in a sequence of steps, each step involving the
modification of the stiffness matrix [K] and ‘φ’ or the load vector P.
Step 6:- Computation of element strains and stresses. From the known nodal displacements, if
required, the element strains and stresses can be computed by using the necessary equations of
solid or structural mechanics. In the above steps, the words indicated in brackets implement the
general FEM step-by-step procedure.
4.3. Convergence requirement:
The finite element method provides a numerical solution to a complex problem. It
may therefore be expected that the solution must converge to the exact formulation of the
structure. Hence as the mesh is made finer the solution should converge to the correct result and
this would be achieved if the following three conditions were satisfied by the assumed
displacement function.
1. The displacement function must be continuous within the element. Choosing polynomials for
the displacement model can easily satisfy this condition.
2. The displacement function must be capable of representing rigid body displacement of the
element. This is when the nodes are given such displacement corresponding to a rigid body
motion; the element should not experience and hence leads to zero nodal forces. The constant
terms in the polynomials used for displacement models would usually ensure this condition.
3. The displacement function must be capable of representing constant strain states within the
element. The reason for the requirement can be understood if we imagine the condition when
the body or structure is divided in to smaller and smaller elements. As these elements
approach infinitesimal size the strain in each element also approach constant strain states. For
one, two and three-dimensional elasticity problems the linear terms present in the polynomials
satisfy the requirement. However, in constant curvature instead of constant strains.

26
4.4. Advantages of FEM:
The properties of each element are evaluated separately, so an obvious advantage is that
we can incorporate different material properties for each element. Thus almost any degree of
non-homogeneity can be included. There is no restriction on to the shape of medium; hence
arbitrary and irregular shapes cause no difficulty like all numerical approximations FEM is based
on the concept of description. Nevertheless as either the variations or residual approach, the
technology recognizes the multidimensional continuous but also requires no separate
interpolation process to extend the approximate solution to every point with the continuum.
One of the important advantages of FEM is that it makes use of boundary conditions in
the form of assembled equations. This is relatively an easy process and requires no special
technology. Rather than requiring every trial solution to satisfy boundary conditions, one
prescribes the conditions after obtaining the algebraic equations for individual’s finite elements.
4.5.Limitations in FEM:
FEM reached high level of development as solution technology; however the method
yields realistic results only if coefficient or material parameters that describe basic phenomena
are available.
The most tedious aspects of use of FEM are basic process of sub-dividing the continuum
of generating error free input data for computer.
4.6. Applications of FEM:
The finite element method was developed originally for the analysis of aircraft structures.
However, the general nature of its theory makes it applicable to wide variety of boundary value
problem in engineering. A boundary value problem is one in which a solution is sought in
domain or region of a body subject to the satisfaction of prescribed boundary conditions.
Finite element method is the best tool in investigation of aircraft structures involving static
analysis of wings, structures of rockets and missiles, dynamic analysis, response to random loads
and periodic loads. In mechanical design, stress concentration problems, stress analysis of
pressure vessels, dynamic analysis of mechanical linkages can be effectively dealt using finite
element method.

27
The specific application of the finite element method in the three major categories of
boundary value problems, namely equilibrium of steady state or time independent problems,
Eigen value problems, and propagation or transient problems. In the equilibrium problems steady
state displacement or stress distribution is found for a solid mechanics problem, temperature or
heat flux distribution in the case of heat transfer problem. Referring to Eigen value problems in
solid mechanics or structural problem, natural frequencies, buckling loads and mode shapes are
found, stability of laminar flows is found if it is a fluid mechanics problem and resonance
characteristics are obtained if it is an electrical circuit problem, while for the propagation or
transient problem, the response of the body under time varying force is found in the area of solid
mechanics.
Finite element method finds its application in the field of civil engineering in carrying out
the static analysis of trusses, frames and bridges. The dynamic analysis of the structure is to
obtain natural frequencies, modes and response of the structures to periodic loads. Nuclear
engineering also uses finite element method concept in the static and dynamic characterization of
its systems such as nuclear pressure vessels, containment structure and dynamic response of
reactor component containment structures. Even the Biomedical engineering applies finite
element method, for impact analysis of skulls. Finite element method can be applied to analysis
of excavation, underground openings and dynamic analysis of dam reservoir systems, which
come under Geomechanics.

28
5. FEA SOFTWARE – ANSYS
5.1. Introduction to ANSYS Program:
Dr. John Swanson founded ANSYS. Inc. in 1970 with a vision to commercialize the
concept of computer simulated engineering, establishing himself as one of the pioneers of Finite
Element Analysis (FEA). ANSYS Inc. supports the ongoing development of innovative
technology and delivers flexible, enterprise wide engineering systems that enable companies to
solve the full range of analysis problem, maximizing their existing investments in software and
hardware. ANSYS Inc. continues its role as a technical innovator. It also supports a process-
centric approach to design and manufacturing, allowing the users to avoid expensive and time-
consuming “built and break” cycles. ANSYS analysis and simulation tools give customers ease-
of use, data compatibility, multi-platform support and coupled field multi-physics capabilities.
5.2. Evolution of ANSYS Program:
ANSYS has evolved into multipurpose design analysis software program, recognized
around the world for its many capabilities. Today the program is extremely powerful and easy to
use. Each release hosts new and enhanced capabilities that make the program more flexible,
more usable and faster. In this way ANSYS helps engineers meet the pressures and demands
modern product development environment.
5.3. Overview of the program:
The ANSYS program is flexible, robust design analysis and optimization package. The
software operates on major computers and operating systems, from PCs to workstations and to
super computers. ANSYS features file compatibility throughout the family of products and
across all platforms. ANSYS design data access enables user to import computer aided design
models in to ANSYS, eliminating repeated work. This ensures enterprise wide, flexible
engineering solution for all ANSYS user.
User Interface: Although the ANSYS program has extensive and complex capabilities, its
organization and user-friendly graphical user interface makes it easy to learn and use.
There are four graphical methods to instruct the ANSYS program:
1. Menus
2. Dialog Boxes

29
3. Tool bar
4. Direct input of commands.
Menus: Menus are groupings of related functions or operating the analysis program located in
individual windows. These include:
1. Utility menu
2. Main menu
3. Input window
4. Graphics window
5. Tool bar
6. Dialog boxes
Dialog boxes: Windows that present the users with choices for completing the operations or
specifying settings. These boxes prompt the user to input data or make decisions for a particular
function.
Tool bar: The tool bar represents a very efficient means for executing commands for the
ANSYS program because of its wide range of configurability. Regardless of how they are
specified, commands are ultimately used to supply all the data and control all program functions.
Output window: Records the ANSYS response to commands and functions
Graphics window: Represents the area for graphic displays such as model or graphically
represented results of an analysis. The user can adjust the size of the graphics window, reducing
or enlarging it to fit to personal preferences.
Input window: Provides an input area for typing ANSYS commands and displays program
prompt messages.
Main menu: Comprise the primary ANSYS functions, which are organized in pop-up side
menus, based on the progression of the program.
Utility menu: Contains ANSYS utility functions that are mapped here for access at any time
during an ANSYS session. These functions are executed through smooth, cascading pull down
menus that lead directly to an action or dialog box.

30
Processors: ANSYS functions are organized into two groups called processors. The ANSYS
program has one pre-processor, one solution processor; two post processors and several auxiliary
processors such as the design optimizer. The ANSYS preprocessor allows the user to create a
finite element model to specify options needed for a subsequent solution. The solution processor
is used to apply the loads and the boundary conditions and then determine the response of the
model to them. With the ANSYS post processors, the user retrieves and examines the solutions
results to evaluate how the model responded and to perform additional calculations of interest.
Database: The ANSYS program uses a single, centralized database for all model data and
solution results. Model data (including solid model and finite element model geometry,
materials etc.) are written to the database using the processor. Loads and solution results data are
written using the solutions processor. Post processing results data are written using the post
processors. Data written to the database while using one processor are therefore available as
necessary in the other processors.
File format: Files are used, when necessary, to pass the data from part of the program to another,
to store the program to the database, and to store the program output. These files include
database files, the results file, and the graphics file and so on.
5.4. Reducing the design and manufacturing costs using ANSYS (FEA):
The ANSYS program allows engineers to construct computer models or transfer CAD
models of structures, products, components, or systems, apply loads or other design performance
conditions and study physical responses such as stress levels, temperature distribution or the
impact of vector magnetic fields. In some environments, prototype testing is undesirable or
impossible. The ANSYS program has been used in several cases of this type including
biomechanical applications such as hi replacement intraocular lenses. Other representative
applications range from heavy equipment components, to an integrated circuit chip, to the bit-
holding system of a continuous coal-mining machine. ANSYS design optimization enables the
engineers to reduce the number of costly prototypes, tailor rigidity and flexibility to meet
objectives and find the proper balancing geometric modifications. Competitive companies look
for ways to produce the highest quality product at the lowest cost. ANSYS (FEA) can help
significantly by reducing the design and manufacturing costs and by giving engineers added
confidence in the products they design. FEA is most effective when used at the conceptual

31
design stage. It is also useful when used later in manufacturing process to verify the final design
before prototyping.
Program availability:
The ANSYS program operates on Pentium based PCs running on Wndows95 or
Windows NT and workstations and super computers primarily running on UNIX operating
system. ANSYS Inc. continually works with new hardware platforms and operating systems.
Analysis types available:
1. Structural static analysis.
2. Structural dynamic analysis.
3. Structural buckling analysis.
a) Linear buckling
b) Nonlinear buckling
4. Structural non linearity’s.
5. Static and dynamic kinematics analysis.
6. Thermal analysis.
7. Electromagnetic field analysis.
8. Electric field analysis
9. Fluid flow analysis
a) Computational fluid dynamics
b) Pipe flow
10. Coupled-field analysis
11. Piezoelectric analysis.
5.5. Procedure for ANSYS analysis:
Static analysis is used to determine the displacements, stresses, strains and forces in
structures or components due to loads that do not induce significant inertia and damping effects.
Steady loading in response conditions are assumed. The kinds of loading that can be applied in a

32
static analysis include externally applied forces and pressures, steady state inertial forces such as
gravity or rotational velocity imposed (non-zero) displacements, temperatures (for thermal
strain). A static analysis can be either linear or nonlinear. In our present work we consider linear
static analysis.
The procedure for static analysis consists of these main steps:
1. Building the model.
2. Obtaining the solution.
3. Reviewing the results.
5.6. Build the model:
Figure 5.1 Schematic Diagram of a Disc brake
In this step we specify the job name and analysis title use PREP7 to define the element
types, element real constants, material properties and model geometry element types both linear
and non-linear structural elements are allowed. The ANSYS element library contains over 80
different element types. A unique number and prefix identify each element type. E.g. BEAM 3,
PLANE 55, SOLID 45 and PIPE 16

33
5.7. Material properties:
Young’s modulus(EX) must be defined for a static analysis .If we plan to apply inertia
loads(such as gravity) we define mass properties such as density(DENS).Similarly if we plan to
apply thermal loads (temperatures) we define coefficient of thermal expansion(ALPX).
5.8 Obtain the solution:
In this step we define the analysis type and options, apply loads and initiate the finite element
solution. This involves three phases:
a) Pre – processor phase
b) Solution phase
c) Post-processor phase
5.8.1. Pre – Processor:
Preprocessor has been developed so that the same program is available on micro, mini,
super-mini and mainframe computer system. This slows easy transfer of models one system to
other. Preprocessor is an interactive model builder to prepare the FE (finite element) model and
input data. The solution phase utilizes the input data developed by the preprocessor, and
prepares the solution according to the problem definition. It creates input files to the temperature
etc., on the screen in the form of contours.
5.8.1.1. Geometrical definitions:
There are four different geometric entities in preprocessor namely key points, lines, areas
and volumes. These entities can be used to obtain the geometric representation of the structure.
All the entities are independent of other and have unique identification labels.
5.8.1.2. Model generations:
Two different methods are used to generate a model:
a) Direct generation.
b) Solid modeling
With solid modeling we can describe the geometric boundaries of the model, establish
controls over the size and desired shape of the elements and then instruct ANSYS program to
generate all the nodes and elements automatically. By contrast, with the direct generation

34
method, we determine the location of every node and size, shape and connectivity of every
element prior to defining these entities in the ANSYS model. Although, some automatic data
generation is possible (by using commands such as FILL, NGEN, EGEN etc.) the direct
generation method essentially a hands on numerical method that requires us to keep track of all
the node numbers as we develop the finite element mesh. This detailed book keeping can
become difficult for large models, giving scope for modeling errors. Solid modeling is usually
more powerful and versatile than direct generation and is commonly preferred method of
generating a model.
5.8.1.3. Mesh generation:
In the finite element analysis the basic concept is to analyze the structure, which is an
assemblage of discrete pieces called elements, which are connected, together at a finite number
of points called Nodes. Loading boundary conditions are then applied to these elements and
nodes. A network of these elements is known as Mesh.
5.8.1.4. Finite element generation:
The maximum amount of time in a finite element analysis is spent on generating elements
and nodal data. Preprocessor allows the user to generate nodes and elements automatically at the
same time allowing control over size and number of elements. There are various types of
elements that can be mapped or generated on various geometric entities.
The elements developed by various automatic element generation capabilities of
preprocessor can be checked element characteristics that may need to be verified before the finite
element analysis for connectivity, distortion-index, etc. Generally, automatic mesh generating
capabilities of preprocessor are used rather than defining the nodes individually. If required,
nodes can be defined easily by defining the allocations or by translating the existing nodes. Also
one can plot, delete, or search nodes.
5.8.1.5. Boundary conditions and loading:
After completion of the finite element model it has to constrain and load has to be
applied to the model. User can define constraints and loads in various ways. All constraints and
loads are assigned set 1D. This helps the user to keep track of load cases.

35
5.8.1.6. Model display:
During the construction and verification stages of the model it may be necessary to view
it from different angles. It is useful to rotate the model with respect to the global system and
view it from different angles. Preprocessor offers this capability. By windowing feature
preprocessor allows the user to enlarge a specific area of the model for clarity and details.
Preprocessor also provides features like smoothness, scaling, regions, active set, etc. for efficient
model viewing and editing.
5.8.1.7. Material definitions:
All elements are defined by nodes, which have only their location defined. In the case of
plate and shell elements there is no indication of thickness. This thickness can be given as
element property. Property tables for a particular property set 1-D have to be input. Different
types of elements have different properties for e.g. Beams: Cross sectional area, moment of
inertia etc. Shells: Thickness Springs: Stiffness Solids: None
The user also needs to define material properties of the elements. For linear static analysis,
modules of elasticity and Poisson’s ratio need to be provided. For heat transfer, coefficient of
thermal expansion, densities etc. are required. They can be given to the elements by the material
property set to 1-D.
5.8.2. Solution:
The solution phase deals with the solution of the problem according to the problem
definitions. All the tedious work of formulating and assembling of matrices are done by the
computer and finally displacements and stress values are given as output. Some of the
capabilities of the ANSYS are linear static analysis, non-linear static analysis, transient dynamic
analysis, etc.
5.8.3. Post – Processor:
It is a powerful user-friendly post-processing program using interactive colour graphics.
It has extensive plotting features for displaying the results obtained from the finite element
analysis. One picture of the analysis results (i.e. the results in a visual form) can often reveal in
seconds what would take an engineer hour to asses from a numerical output, say in tabular form.
The engineer may also see the important aspects of the results that could be easily missed in a

36
stack of numerical data. Employing state of art image enhancement techniques, facilities viewing
of:
a) Contours of stresses, displacements, temperatures, etc.
b) Deform geometric plots
c) Animated deformed shapes
d) Time-history plots
e) Solid sectioning
f) Hidden line plot
g) Light source shaded plot
h) Boundary line plot etc.
The entire range of post processing options of different types of analysis can be accessed through
the command/ menu mode there by giving the user added flexibility and convenience.

37
6. DISC BRAKE CALCULATIONS:
6.1. Assumptions:
1. The analysis is done taking the distribution of the braking torque between the front wheel and
rear wheel is 32:68
2. Brakes is applied on all the front wheel only.
3. The analysis is based on pure thermal loading. The analysis does not determine the life of the
disc brake.
4. Only ambient air-cooling is taken in to account and no forced convection is taken.
5. The kinetic energy of the vehicle is lost through the brake discs i.e. no heat loss between the
tyres and the road surface and the deceleration is uniform.
6. The disc brake model used is of homogenous material.
7. The thermal conductivity of the material used for the analysis is uniform throughout.
8. The specific heat of the material used is constant throughout and does not change with the
temperature. 9. Heat flux on each front wheel is applied on one side of the disc only.
6.2. CALCULATION FOR INPUT PARAMETERS:
In the aspect of the car accident prevention, the braking performance of vehicles has been
a critical issue. The rotor model heat flux is calculated for the car moving with a velocity 27.77
m/s (100kmph) and the following is the calculation
Procedure: Data:
1) Mass of the vehicle = 300 kg
2) Initial velocity (u) = 22.22 m/s (80 kmph)
3) Vehicle speed at the end of the braking application (v) = 0 m/s
4) Brake rotor diameter = 0.262 m
5)
staic front axle load
total motor cycle load
=(γ)=0.3
6) Percentage of kinetic energy that disc absorbs (90%) k=0.9
7) Acceleration due to gravity g =9.81m/s2
8) Coefficient of friction for dry pavement μ=0.45.

38
(a) Energy generated during braking:
K.E. =γk
m(u−v)2
2
(b) To calculate deceleration time:
v = u + at
Deceleration time = Braking time = 5s
(c) Braking Power: Braking power during continued braking is obtained by differentiating
energy with respect to time
Pb=
K.E.
t
(d) Calculate the Heat Flux (Q): Heat Flux is defined as the amount of heat transferred per unit
area per unit time
Q =
Pb
A
Table6.1: Calculation for Input Parameters
Formulae Disc design
Stainless
steel
Cast iron
Kinetic energy K.E. =γk
m(u−v)2
2
For all models 20958.021 J 20958.021 J
Deceleration
time
v = u + at For all models 5 sec 6 sec
Braking Power Pb=
K.E.
t
For all models 4191.60 W 3493 W
Calculate the
Heat Flux
Q =
Pb
A
Model 1 𝐴1=0.01473𝑚2
142281.20
W/𝑚2
118567.67
W/𝑚2
Model 2 𝐴2=0.014145𝑚2
148165.58
W/𝑚2
123471.32
W/𝑚2
Model 3 𝐴3=0.014939𝑚2
140290.66
W/𝑚2
116908.88
W/𝑚2

39
6.3. ANALYTICAL TEMPERATURE RISE CALCULATIONS:
The contact area between the pads and disc of brake components, heat is generated due to
friction. For calculation of heat generation at the interface of these two sliding bodies, two
methods are suggested on the basis of “law of conservation of energy which states that the
kinetic energy of the vehicle during motion is equal to the dissipated heat after vehicle stop”. The
material properties and parameters adopted in the calculations are as shown in table.
Table.6.2: Material Properties for Stainless Steel and Cast Iron
Material Properties Stainless Steel (Model I) Cast Iron (Model II)
Thermal conductivity(w/m k) 36 50
Density , ρ (kg/m3) 7100 6600
Specific heat , c (J/Kg ϲ ) 320 380
Thermal expansion , α (10-6 /
k )
0.12 0.16
Elastic modulus, E (GPa) 210 110
Coefficient of friction, μ 0.5 0.5
Film co-efficient h(w/km2 ) 240 280
Operation conditions
Angular velocity,( rad /s) 50 50
Braking Time Sec 5 6
Hydraulic pressure, P (M pa) 1 1

40
7. FEM MODELS OF BRAKE DISC WITH MESHING
Model 1:
Figure 7.1: Meshing of Model 1
Sizing
Relevance Center Fine
Element Size Default
Initial Size Seed Active Assembly
Smoothing Medium
Transition Fast
Span Angle Center Coarse
Minimum Edge Length 2.5e-004 m
Statistics
Nodes 53771
Elements 29243

41
Model 2:
Figure 7.2: Meshing of Model 2
Sizing
Smoothing Medium
Transition Fast
Statistics
Nodes 52632
Elements 28833

42
Model 3:
Figure7.3: Meshing of Model 3
Sizing
Smoothing Medium
Transition Fast
Statistics
Nodes 54667
Elements 30092
Mesh Metric None

43
8. RESULTS
8.1. Stainless Steel: Model No. 1
Figure8.1: Temperature distribution plot for SS Model No. 1
Figure8.2: Heat flux plot SS Model No. 1

44
Model No. 2:
Figure8.3: Temperature distribution plot SS Model No. 2

45
Model No. 3:
Figure8.5: Temperature distribution plot SS Model No. 3

46
8.2. Cast iron: Model No. 1
Figure8.7: Temperature distribution plot CI Model No. 1
Figure8.8: Heat flux plot CI Model No. 1

47
Model No. 2

48
Model No. 3

49
9. DISCUSSION
From the figures, given above, we can summarize the results in the following manner: -
Table no. 9.1 Maximum and minimum Temperature Distribution
Results
Temperature Distribution
( o
C )
Material Stainless Steel Cast Iron
Min Max Min Max
Model No.1 72.11 225.32 86.425 181.74
Model No.2 48.399 261.21 75.615 173.25
Model no.3 49.09 246.66 75.645 165.03
Table no. 9.2 Maximum and minimum Total Heat Flux
Results
Total Heat Flux
(W/m2
)
Material Stainless Steel Cast Iron
Min Max Min Max
Model No.1 503.14 2.61×105
671.23 2.55×105
Model No.2 449.5 2.99×105
1239.2 3.51×105
Model no.3 489.94 3.05×105
1263.3 3.05×105

50
10. CONCLUSION
From our study of various design patterns for different materials we have observed that
the maximum temperature rise for cast iron is much less as compared to stainless steel and thus
on the basic of thermal analysis, cast iron is the best preferable material for manufacturing disc
brake. However cast iron disc brake suffers a drawback of getting corroded when it comes in
contact with moisture and hence it cannot be used in two wheeler and thus we prefer stainless
steel.
Heat dissipation from disc brake also depends on the type of design pattern used. The
different design patterns studied are:-
A) Model No. 1- With more no. of circular holes
B) Model No. 2- With kidney shaped holes
C) Model No. 3- With less no. of circular holes
Among the above models best heat dissipation is observed for model 1 consisting large
number of holes and made of stainless steel.

51
REFERENCE
1. “Brakes and Dynamometer”-Theory of Machine by R.S. Khurmi & J.K. Gupta-732.
2. “Heat Transfer”- D.S. Pavaskar & S.H. Chaudhari.
3. “Thermal analysis guide”-
http://orange.engr.ucdavis.edu/Documentation12.0/120/ans_the.pdf
4. “Disc Brake” - http://en.wikipedia.org/wiki/Disc_brake
5. “Structural and Thermal Analysis of rotor disc brake”-
http://core.ac.uk/download/pdf/9554608.pdf

52
ACKNOWLEDGEMENTS:
It gives me immense pleasure to convey my sincere thanks to all those who have
contributed their efforts in completion of this seminar. Specific thanks to my guide Dr. R. K.
Shrivastava, for getting the work started and putting me on the methodical line of thinking. Her
technical guidance and timely suggestions have helped me a lot throughout. This report has been
an ambitious work from start and would never have been completed without the co-operation of
the concerned teachers.
We shall be failing in my duty if I do not express my gratefulness to our Mechanical staff
members for their never ending help in the form of advice right through the execution of the
report. Lastly, I pay my special appreciation to all my dear friends and colleagues for their time
to time encouragement.
PENGKAM K. LUNGCHANG (BE06F02F065)
PARAG DESHATTIWAR (BE10F02F068)
TOSHIF RUIKAR (BE11F02F046)
KAHANI MENJO (BE11F02F064)
SANJEET KUMAR (BE11F02F065)
B.E. MECHANICAL

Thermal analysis of brake disc 2015

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Thermal analysis of brake disc 2015

Similar to Thermal analysis of brake disc 2015 (20)

Recently uploaded

Recently uploaded (20)

Thermal analysis of brake disc 2015