Performance Analysis on Disc Brake of Super Bikes

Performance Analysis on Disc Brake of Super Bikes

A. Vennila M. Mohamed Ariffuddeen

B.E. Mechanical Engineering A/P Mechanical

SNS College of Technology SNS College of Technology Coimbatore, India Coimbatore, India

Abstract:- The disc brake is a device for slowing or stopping the rotation of a wheel. Repetitive braking of the vehicle leads to heat generation during each braking event. Transient Thermal and Structural Analysis of the Rotor Disc of Disk Brake is aimed at evaluating the performance of disc brake rotor of a car under severe braking conditions and there by assist in disc rotor design and analysis. Disc brake model and analysis is done using ANSYS workbench 16. The main purpose of this study is change the structure of the brake disc by providing a hole from top position. The atmospheric air is supplied through the hole, due to this changing the thermal conductivity is decreased and we reduce the high temperature formation.

INTRODUCTION:

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. 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. Most drum brake designs have at least one leading shoe, which gives a servo-effect. Drums are also prone to "bell mouthing", and trap worn lining material within the assembly, both causes of various braking problems.

BRAKE DISC:

The brake disc is the component of a disc brake against which the brake pads are applied. The weight and power of the vehicle determines the need for ventilated discs.[13]The "ventilated" disc design helps to dissipate the generated heat and commonly used on the more-heavily-loaded front discs.

BRAKE FAILURE CAUSES:

• Before you can understand brake failure, you must understand how brakes work.

• The brake system is rather like this children's song verse, "The head bone's connected to the neck bone, the neck bone's connected to the shoulder bone. In vehicles, the brake pedal is connected to the pistons, and the pistons are connected to the brakes. Most modern cars have disc front brakes and drum rear brakes.

• Functioning brakes stop a vehicle by using friction. In this way, they are unlike the engine, which must always be kept lubricated to run smoothly. In front brakes, friction stops the brake calipers and pads. In rear brakes, friction hits the brake drums and shoes.

• Several factors can interfere with this friction and lead to brake failure:

• Grease or oil on brakes causes brake failure, because it interferes with friction. If oil leaks, it may indicate that an oil seal has failed.

  DANGERS OF BRAKE FAILURE:

• Brakes function because of a special hydraulic, or liquid-based, system. Brake fluid moves from the pedal through the brake-line system. Because liquids can't be compressed, they move. It is this movement that pushes against the mechanism that stops the vehicle. So when this fluid runs low, brake problems will occur.

• The most apparent danger in brake failure is the possibility of injury or death. As a result, it is important to wear a seat belt and to be certain that guidelines for infant and child car seats are met to ensure safety. Don't forget to be alert to and aware of pedestrians on or near the roadway.

• Another concern is property damage. This includes the vehicle itself but also trees, power lines, highways signs and telephone poles. Damage to private or public property will need to be compensated, which can affect your auto insurance premium.

• Don't let the dangers of brake failure frighten you. Read on to learn what you can do in the event of brake failure.

  MANUFACTURING OF BRAKE DISC:

  Introduction:

  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:

• Metal casting

• Metal cutting

• Metal forming and shaping

• Fabrication and welding

The disc brake system is one important system to look at since it is not only used in automotive industries but also in locomotives and in jumbo jets as well and hence elaborating more on disc brake system, the main components of a disc brake are the Brake disc or Rotor, Brake pads, Caliper.

In this report I would be hoping to elaborate more about the brake disc (rotor) and how it is manufactured, the materials used and its quality and defects compared to other brake.

COMPARISON OF MECHANICAL PROPERTIES

It is observed from the comparison of results that the mechanical properties of hybrid aluminum composite is superior to the monolithic Aluminum metal.

Disc brake is an assembly product and these parts are manufactured separately through different procedure to one another.

EQUIPMENT/TOOLS USED FOR MANUFACTURING

The equipments and tools used in this process will be talked more about in the manufacturing details section of this report but some of the main tools used in as follows:

• Permanent molds

• Crucibles

• Drilling machines

• Computer guided machines

  Chemical composition:

  Hardness -Hardness is the resistance to surface indentation (e.g., a local dent or scratch). Thus, it is a measure of plastic deformation. The Hardness of the composites samples were measured using a Leitz, Brinnel hardness measuring machine with a load of 100 N. The specimen prepared as per ASTM standard and the dimension of the specimen is 19X19 mm Wear–Wear test is carried out with pin-on disc setup with ASTM standard dimension. To check the wear rate on different loading conditions.

  THE MODEL DESIGN AND BRAKING CONDITIONS

  Design Consideration

• Brake Power

• Larger diameter rotors more will be brake power with the same amount of clamp force than a smaller diameter rotor.

• The higher the coefficient of friction for the pad, the more brake power will be generated

• Dynamic Coefficient Of Friction

• Type of material used for the brake rotor.

• Speed Sensitive Coefficient of friction typically drops as the speed of the vehicle increases

• Pressure Sensitive – Coefficient of friction typically drops as more clamp force is generated.

• Temperature Sensitive – Coefficient of friction typically drops as the temperature of the brake system increases.

• The more surface area available on a brake system, the better heat dissipation will be via convection.

• Material Selection Material selection is important in trying to control where the heat dissipates once generated

• Wear wear is proportional to pressure intensity

  (p) and relative velocity (v) which is proportional to radius. Thus W=k p r

• Thermal Mass Must have enough material mass to properly handle the temperatures during braking applications. This is liited by size and weight.

Front View

Side View New Design:

Isometric view and side view

THERMAL ANALYSIS:

Thermal L Analysis is probably the most common application of the finite element method. Thermal analysis to calculate the heat flux, temperature gradient & temperature variation. For finite element Analysis of Engine Head, SOLID92- Tetrahedral element has been used.

RESULT VALUES FOR NORMAL CHEMICAL COMPOSITION OF Fe

(Carbon (C) and silicon (Si) 2.14 wt. % and 13 wt%, Remaining iron

IMPORTING GEOMETRY:

Material Data Cast Iron TABLE

Cast Iron > Constants

Meshing Geometry:

Steady-State Thermal (A5) TABLE

Model (A4) > Analysis

TABLE 7

Model (A4) > Steady-State Thermal (A5) > Initial Condition

TABLE 8

Model (A4) > Steady-State Thermal (A5) > Analysis Settings

BOUNDARY CONDITION:

TABLE

Model (A4) > Steady-State Thermal (A5) > Loads

6. RESULT VALUES:

Thermal Distribution

Results

Minimum 22.116 °C

Maximum 50. °C

Thermal Error;

Model (A4) > Steady-State Thermal (A5) > Solution (A6)

> Results

RESULT OF MODIFIED DESIGN:

Analysis Result for disc brake which is having hole in with of disk brake which is pass through inner part of the disc by using components we analyzed and result are defined.

Convection boundary conditon for new design :

Temperature distribution ;

Thermal error:

Model (A4) > Steady-State Thermal (A5) > Solution (A6) > Resu

CONCLUSION

By this method the life time of the disc wheel can be increased in a specific manner. It is also has many advantages in the modern world since the cost of the disc brake in future will be in higher most position so by applying the modern techniques and modern methods the efficiency and life time is increased because of prevention of hot spots. Our Analysis of Disc Brake on the sport bikes enhances the perfect result to the desired level. The method can be applied by changing the structure either by changing the composition of disc wheel. The structure of the disc wheel can be changed by drilling the hole in the upper most position in the specific diameter.

REFERANCE:

1. Mesut Duzgun Investigation of thermo-structural behaviors of different ventilation applications on brake discs Journal of Mechanical Science and Technology 26 (1) (2012) 235~240.

2. M. K. Khalid, M. R. Mansor, S. I. Abdul Kudus, M. M. Tahir, and

   M. Z. Hassan Performance Investigation of the UTeM EcoCar Disc Brake System International Journal of Engineering & Technology IJET-IJENS Vol: 11 No: 06. December 2011.

3. Gnanesh P, Naresh C and Syed Altaf Hussain FINITE ELEMENT ANALYSIS OF NORMAL AND VENTED DISC BRAKE ROTOR International Journal of Mechanical Engineering & Robotics Research 2014 ISSN 2278 0149 www.ijmerr.comVol. 3, No. 1, January 2014

4. Ameer Shaik and Lakshmi Srinivas,Structural and Thermal Analysis of Disc Brake Without Cross-drilled Rotor Of Race Car, International Journal of Advanced Engineering Research andStudies,2012 , Vol.I, Issn 2249-8974, pp 39-43

5. D. B. Antanaitis and A. Rifici, The effect of rotor cross drilling on brake performance (2006) SAE, 2006-01-0691, 571-596.