ACTIVE BRAKE COOLING 89 - My Design Projects · ACTIVE BRAKE COOLING 89 ... The introduction to the engineering design focus is ... ACTIVE BRAKE COOLING 91 Figure 1 Race Car

ACTIVE BRAKE COOLING 89

Appendix M: Finite Element Analysis

ABSTRACT

The Purpose of this report is to show how finite element analysis is a method and

technique used to solve a variety of engineering design application problems through the

utilization of the powerful Lisa software. The introduction to the engineering design focus is

given on pages 3-5 of this technical report where the mechanical engineering design is an active

cooling conditioning and monitoring system for heavy transportation vehicles.

The demand for this system is such that will aid and abide in the shipping and distribution

industry offering a safer means of transporting goods on commercial highways where accidents

due occur from a scientific phenome called brake fade.

The thermal analysis of a radial cross section plate Is approximated as a flat plate or

plane wall that is subjected to boundary conditions having a temperature of 560 degrees

Celsius on the interior surface and a temperature of 20 degrees Celsius on the external

surface.

The analytical analysis will be performed by conducting sequential integration of the

second order linear homogenous differential equation by solving for the integration constants and

formulating a general solution this detail is modeled on pages 6-8.

The finite element analysis will be conducted utilizing Lisa software and boundary

conditions at the 2dimensional solid 4 element 5 node body. Where the known temperatures at

the nodes on the y=o axis are 560 degrees Celsius and the temperatures at the y=L axis are

20 degrees. The mechanical properties of the grey cast iron h250/g3000 plate are given in

table 1 on page 5. The actual conditions that a brake drum experiences at critical temperatures

are give in table 2 located on page 5. The full analysis of the drum and the purpose of offering

forced convection through the design of an active cooling conditioning and monitoring brake

system with air as a fluid medium are beyond the scope of this report.

The convergence test is shown in table 7 located on page 10 of this technical


report.

TABLE OF CONTENTS

ABSTRACT………………………………………………………………………………………………………………………..…Page1

TABLE OF CONTENTS…………………………………………………………………………………………………….......Page2

INTRODUCTION…………………………………………………………………………………………………………….…Page3-5

ANALYTICAL ANALYSIS…………………………………………………………………………………………………….Page6-8

FINITE ELEMENT ANALYSIS……………………………………………………………………………………..……….Page8-9

CONCLUSION……………………………………………………………………………………………………………………Page10

REFERENCES……………………………………………………………………………………………………….…………….Page11

DOCUMENTS…………………………………………………………………………………………………………………...Page12


Figure 1

Race Car

Application

Page 3

Figure 2

Air Plane

Application

Page 4

Figure 3

Transport Truck

Application

Page 4

Figure 4

Temperature

Distribution

Page 8

Table 1

Mechanical Properties of

grey cast iron H250/g3000

Page 5

Table 2 Loading Conditions Page 5

Table 3 Temperature Distribution Page 7

Table 4 Node ID Page 8

Table 5 Element ID Page 8

Table 6 Results Page 9

Table 7 Convergence Page 10

INTRODUCTION

Heavy Transportation vehicles are requested in industry to transport a variety of goods to a variety of

locations. Some of these goods are simple goods that individuals encounter everyday such as products

from the grocery that have been processed and packaged or goods such as stationary items that are

used in professional office settings. On the other end of the spectrum with respect to the variety of

goods that are requested to be shipped from location to location by heavy transportation vehicles, some

of these goods can be of a significant amount of weight increasing the loading of the heavy


transportation vehicles which of course increases the demand of the engine and other mechanical

related components and attributes on these vehicles. Such as lubrication, fuel, and braking power.

Brake Fade is a Phenomena that occurs in various types of vehicles, such as race cars, air planes, and

transport trucks. Brake fade occurs when the temperature of the braking element – disc or

drumreaches a temperature that causes a volume increase due to thermal expansion requesting more

work from the braking piston. Brake fade occurs when the brake pad combusts from the release of a

gaseous substance degenerating the quality of braking performance. Brake fade occurs when the

braking effort is not equally distributed requesting more work to be done by the braking piston. A

general misconception for brake fade occurs when the braking fluid reaches a temperature that causes

a thermodynamic state transformation from liquid to vapor again degenerating the quality of braking;

however, for terms of this technical finite element analysis project report, Vapor Brake fade is not a

primary focus.

Race Cars

Figure One

• Brakes: 6-piston (front and rear) carbon calipers, carbon discs and pads

• Brake disc size: 278 x 28 mm (front and rear)

• Weight 642 kg

Figure One shows a Formula One race car making a sharp turn around the competitive race track.

Formula One race cars like the one depicted in figure one reach top speeds up to 360 Km/h. These

speed request heavy quality braking that avoids the brake phenome brake fade. Air Planes


Figure Two

Figure Two shows a plane running off the landing strip. Landing speeds for typical airplanes are 250300 miles per hour with a weight of 391000 kg, the request is for quality braking without the occurrence of the mechanical phenome brake fade.

Transport Trucks

Figure Three

Figure three is shows a heavy transportation vehicle transporting an over-sized load that is vulnerable to

suffering brake fade at quick braking such as when travelling through a steep decline through a

gravitational field

The focus of the capstone mechanical engineering design project is “to design an active conditioning and

monitoring cooling system” for heavy transportation vehicles.

Finite Element Analysis from the software Lisa will show the stresses that the brake drum is subjected to

at high stress levels.

Table 1


Modulus of Elasticity 150 Gpa

density 7100 kg/m^3

Poisson ratio 0.26

thermal conductivity 53 W/m K

specific heat 0.46 kJ/kg*K

Thermal Expansion

coefficient 1.1*10^-5

⁰C^-1

Convection Heat

Transfer Coefficient of 800

W/m^2⁰C

Heat Flux Acting on the inner

surface

1607

Kw/m^2

Tabulated in table 1 are the mechanical properties of the grey cast iron ht250/g3000 drum where the

Modulus of Elasticity is 150 Gpa, the density is 7100 kg/m^3, the poisons ratio is 0.26, the thermal

conductivity is 53 W/mK and the specific heat is 0.46 kJ/kg K, the thermal expansion coefficient is

1.1*10^5 /⁰C.

Table 2

Parameter Quantity Detail Calculations

Centrifugal force 97055819.79N density * outer radius of drum *(w^2)

Speed (rotation) (z axis) 164.04 rad/s Velocity / inner radius = 120km *(1000/3600)/ (0.2032)

Internal Temperature 560⁰C due to friction

Temperature of air 20⁰C close to room temperature


Gravity (-y direction) 9.81 m/s^2 Gravitational force due to acceleration


Braking Pressure 680000 Pa Applied Braking Pressure

Inner Surface Area of drum 0.220537m^2 To Scale inner surface area of the drum

Surface Force 149965.16N Corresponding Surface Force

inner radius of drum 0.2032m To Scale inner surface area of the drum

outer radius of drum 0.508 m To Scale outer surface area of the drum

Tabulated in table two are conditions that a brake drum experiences at the critical temperature

560⁰C along with the geometry layout.


Analytical Analysis

Modelling a thick plate cross section as a plane wall to simplify the analysis and to test

convergence using an Analytical Method.

Free Body Diagram

Surface Area = Projected length of the Z axis * L = 0.15875*0.0635 =0.010008m^2

The quantities of interest to be determined are the heat flux acting on the surface generated by

the friction braking pressure of the brake pad relative to the drum surface where x=0m, as well as

the temperature distribution throughout the cross section of the drum in the lateral direction.

The Thermal Properties are given in Table 1.

Assumptions:

• Steady State Heat Conduction

• One Dimensional Heat Conduction

• Thermal conductivity is constant • No heat is generated


The second order linear homogenous differential equation

The corresponding boundary conditions

Performing sequential integration

The general solution is the correspond linear straight line linear combination

Applying Boundary Condition

solving for the constants of integration

Substituting into the general equation Leads to the temperature distribution profile


Table 3

Tabulated in table 3 are the temperature at each position of x (m) using a step size of 0.00222


Figure 4 is a visualization of the temperature distribution through the Cross- Section Plate. Now

determining the rate of heat conduction from Fourier’s Law


Finite Element Analysis

Modelling the thick plate cross section as a plane wall to simplify the analysis and to test

convergence using a Finite Element Method software Lisa.

Table 4

Table 5

2-Dimensional Analysis of a thick plate in a spatial reference frame to be analyzed under the

nodal temperature conditions using. Table 4 and Table 5 represent the location of the 5 nodes for

the 4 tri3 elements.


Table 6

Tabulated in table 6 are the corresponding temperatures at node1, node2, node3, node4, and node5

With the corresponding heat flux at each node in the x direction and the corresponding heat flux in the y

direction.

The Temperature distribution is shown in color coding representing the various temperatures as a

function of location in the y direction


Conclusion

Temperature at Heat flux at

x=L/2 (⁰C)

Surface of the

plate (W/m^2)

Finite Element

Method

290

1609673.79

Analytical Method 290 1607000.00

Relative Error 0 0.00167

Table 7

Tabulated in Table 7 are the results of both the finite element method using Lisa

software, and the analytical method. The relative error for the temperature at location

X=L/2 is 0, and the relative error of the heat flux at the surface of the plate is 0.00167.

Another interesting observation is that the assumption that heat transfer is only is one

direction is a very good assumption and is scientifically verified as results indicate in

column three of table 6 because the heat flux is significantly small that it can be

disregarded completely. Lisa Software is a powerful tool that can aid in the mechanical

engineering design applications


REFERENECES

Daryl Logan a First Course in Finite Element Using Algor

Dr. Bai’s ENGI-0450-WA Lecture Notes

Wikipedia

Engineering Tool Box

Yunus Cengal & Ghajar Heat and Mass Transfer Fundamentals and Applications

http://www.grantex.gr/index.php?page=&table=brake_shoe&keyword=&q=brake%20shoe&vehicle_axl

e_manufacturer=&start=15&field=&order=ASC&orderby=application&lang=en

http://fenton.trpparts.com/media/1018/2013-aug-fab-trp-drums.pdf

http://www.carquestprofessionals.com/catalogs/fleet_hd/HFF_CARQUEST_Friction_2011.pdf

http://www.grantex.gr/index.php?page=&table=brake_shoe&keyword=&q=brake%20shoe&vehicle_axle_manufacturer=&start=15&field=&order=ASC&orderby=application&lang=en




















DOCUMENTATION

The purpose of this section is to show the drum illustrated in the figure below to be modelled

and analysed using ANSYS WORKBENCH. Under the loading mentioned similar to table two

with mechanical properties of structural steal again which is similar to that mentioned in table

1.

Generating the Mesh

Selecting appropriate elements for specified regions to match the physical behavior of the

system is an important aspect of modelling in engineering applications. Finer Elements should

be used closer to geometric discontinuities such as abrupt changes in cross section or around

sensitive areas. The closer the mesh models the physical system the more accurate the solution

will be. The Aspect Ratio is optimal when equality is 1. This is because of the more precise

configuration of the element.

This Figure shows a very good resolution of fine mesh that has been generated. The top left

corner displays the Aspect Ratio which can be shown that the majority of the mesh is less than

4. The bottom right hand corner shows the scale in units of m.


This Figure Illustrates the meshing that was configured utilizing the software LISA.

The Figure above is the same Drum with a mesh that has been generated however the coarse is

mesh. Notice the increase in the Aspect Ratio.

AN EMAIL are the solutions to the problem where fixed supports are located at each of the 10 holes as

well as the axel entry. The results show the detail of the stress and deformation, and temperature

distribution The accuracy of these values are dependent on the accuracy of the geometry configuration,

the mesh, and the in-service loading conditions.

Appendix N: Lumped System Analysis

Objective


Determine the velocity required to keep the surface of the inner surface of the drum at safe

temperatures

Analysis

Prevention through Design with lumped system analysis which requests that the temperature of a lumped

body is a function of time. T(t), such as an egg that is being boiled or cooled for consumption.

The brake drum is required to have a maximum in service condition of 427⁰C

Assume braking starts at 120 km/h and decreases to 0

Conclusion

Once the velocity is known that will maintain the temperature at safe limits, sizing of outlets of

piping can be determined and the corresponding volume flow rate can be determined and the

corresponding power can be determined for an accurate blower.

Lumped System Analysis is not a valid technique for this analysis because it violated the

condition of keeping the Biot number less than <0.1 even with significant adjustments such as the

rotations of the braking wheel, the linear velocity of the wheel.

Reference

Page 243 chapter 4 Heat and Mass Transfer Fundamentals Applications

Excel Work



Appendix O: Bill of Materials



Appendix P: Final Gantt Chart






Appendix Q: Work Breakdown Structure

April 11 2017 Involved

TASKS STU ZACH JOHN -ALLAN STATUS

MIDTERM PROGRESS REPORT x x x COMPLETE

PRELIMINARY DESIGN x x x COMPLETE

PROTOTYPE/ APPARTUS

CONSTRUCTION

x x x COMPLETE

ID. KEY PERFORMANCE INDICATORS x x x COMPLETE

List Constraints/Limitations of

Applications

x x x COMPLETE

AHP ANALYSIS FOR COOLING

MEDIUM

x x x CANCELLED

CON. LABORATORY EXPERIEMENTS x x x CANCELLED

BILL OF MATERIAL x x x COMPLETE

MAKE CONTACT WITH

FIN.SPONSOR (CLIENT IS FIN

SPONSOR)

x x x COMPLETE

COMPLETE WHIMIS SAFETY

TRAINING

x x x COMPLETE

COST/BUDGET ANALYSIS x x x COMPLETE

WEEKLY TEAM MEETINGS x x x COMPLETE

DRAFT REPORT x x x COMPLETE

LOG BOOK KEEPING x x x COMPLETE

WORD FORMATTING x x x COMPLETE PENDING

TREASURING DUTIES x x x CANCLLED

I.P RESEARCH DATA BASE x x x COMPLETE

BOOK LAB TIMES MAKE CONTACT

WITH Mr.Keilash

x x x COMPLETE

COMMUNICATE THROUGH EMAIL

WITH SUPERVISOR

x COMPLETE

LIST ADVANTAGES DISADVANTES

OF CURRENT MODELS FOR

PRESENTATION AND REPORT

x x x COMPLETE

IDENTIFY WAYS TO GATHER

PHYSICAL RESOURCES (OBTAIN

COMPONENTS)

x x x COMPLETE


PUMP ASSEMBLY ANALYSIS x COMPLETE

QUENCHING ANALYSIS x COMPLETE

CONDITIONING AND MONITORING

ANALYSIS

x COMPLETE

MECHATRONICS DESIGN x COMPLETE

PUMP ASSEBMLY DESIGN x COMPLETE

PROJECT MANAGEMENT /FLUID

MEDIUM/ APPLICATIONS

x COMPLETE

THE MAJOR PHASES OF THE

PROJECT ARE:

COMPLETING THE PRELIMINARY

DESIGN Of AN EXPERIMNTAL

APPARATUS WILL CAUSE A

TRANSITION INTO THE AREA OF

THE PROJECT WHERE WE CAN

FOCUS NOT ONLY AS A TEAM ON

THE FINAL DESIGN BUT ON OUR

INDIVIDUAL CONTRIBUTIONS

COMPLETE

RECEIVING FEEDBACK FROM OUR

SPONSOR REGARDING THE

PROPE+OSAL AND THE PROJECT

OUTLINE WILL ASSIST IN

NARROWING DOWN THE SCOPE OF

THE PROJECT

ACTIVE

MAKING CONTACT WITH A

FINANICAIL SPONSOR WILL ALLOW

US TO DO A PROPER COST

ANALYSES AND GIVE US A SENSE OF

SECURITY BY RAISING TEAM

MORAL CLIENT IS ACTING AS FIN

SPONSOR

COMPLETE

CONDUCTING LABORATORY

EXPERIMENTS WILL PROVIDE US

WITH OPTIMAL PERFORMANCE

INDICATORS AND PRESENT

ADDITIONAL INFORMATION THAT

WILL BE APPLIED DIRECTLY TO

DESIGN APPLICATIONS

CANCELLED


AS WEEKLY TEAM MEETINGS

PROGRESS OUR TEAM WILL

DEVELOP CONFIDENCE WITH OUR

OWN STRENGTHS AND TRUST WILL

BE GENERATED TO ENSURE

QUALITY WORK

ACTIVE

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ACTIVE BRAKE COOLING 89 - My Design Projects · ACTIVE BRAKE COOLING 89 ... The introduction to the engineering design focus is ... ACTIVE BRAKE COOLING 91 Figure 1 Race Car