INTEGRATED POLYTECHNIC REGIONAL CENTER

KICUKIRO CAMPUS

MECHANICAL ENGINEERING DEPARTMENT

AUTOMOBILE TECHNOLOGY PROGRAM

CERTIFICATE

The project work presented in this title, STUDY OF TURBOCHARGER FOR TWO WHEELS,

is a record of the original work done by MUTSINZI Théogène, RUSINGIZA Eric and

TUYISHIME Dieudonne (Reg. n0 Gs/2009/0182, Gs/2009/0204 and Gs/2009/0066) in partial

fulfillment of the require for the award of Advanced Diploma in Mechanical Engineering at the

Integrated Polytechnic Regional Center (IPRC).

Supervisor Head of Department of Mechanical Engineering

NDAHAYO Edmond HAVUGWEKONSILE STANISLAS

Date 1 /09 /2012 Date 1/09/2012

Signature…………… Signature……………..

Submitted to the project examination held at IPRC on ……. /……. /2012

i

DECLARATION

We, MUTSINZI Théogène, RUSINGIZA Eric and TUYISHIME Dieudonne , declare that

content of this dissertation is our original work and it is a contribution to the fulfillment of the

requirement for the award of advanced diploma of technology mechanical engineering . We do

declare to the best of our knowledge that this research is original and has never been presented or

submitted for any academic award in any university or our college as a whole or in part.

Date ……. / ……/ 2012

MUTSINZI Théogène

RUSINGIZA Eric

TUYISHIME Dieudonne

ii

DEDICATION

We dedicate this report work to our beloved families, our brothers and sisters, our lectures, our

supervisors and all friends of us, to the government of Rwanda.

iii

LIST OF ABBREVIATIONS

RPM: Revolution Per Minute

IV: Inlet Valve

EV: Exhaust Valve

TDC: Top Dead Center

BDC: Bottom Dead Center

CA: Crankshaft Angle

TEVSA: Technical Vocation Schools Associations

CID: Cubic Inch Displacement

VE: Volumetric Efficiency

CFM: Cubic Feet Per Minute

PB: Pressure Boost

PR: Pressure Ratio

V: Volume

A: Area

Q: Flow Rate

ρ: Density

m: Mass

a: air

w: water

CP: Specific Heat

iv

IAT: Inlet Air Temperature

NOX: Oxide of Nitrogen

HC: Hydrocarbon

CO: Oxide Of Carbon

VTC: Vocation Training Center

PSI: Pound per Square Inch

AFR: Air Fuel Ratio

ECU: Electronic Control Unit

Q1=Flow rate

Q2 =Heat transfer

v

ACKNOWLEDGEMENT

We would like to express our deepest gratitude to our supervisor Mr NDAHAYO Edmond for

their marked role in restructuring our work and guiding us through to recent approach in the

study theme. Their insight comments for the betterment of the whole work were appreciable.

We are also grateful to Mr. HAVUGWEKONSILE Stanislas head of Mechanical Department

to give the relevant information related to our work and giving construction comments and

suggestions from the very inception of the work.

We cannot forget our classmates’ for the knowledge we shared and the brotherhood they showed

us in all of academic activities.

We would also like to thank everybody who contributes for the realization of our memoir.

MAY GOD BLESS YOU ALL!

vi

ABSTRACT

It is normal practice for every institution of high learning that the student in the final year of any

level of studies write a project work or a dissertation as part of the requirement for the award of

A1 DIPLOMA in their respective faculties. It is for this particular reason why as the member of

our group still student of Kicukiro College of Technology, we have written this project entitled

STUDY OF TURBOCHARGER FOR TWO WHEELS.

The writing of this project has helped the author to deeply and considerably understand the

theories obtained from the lectures. It has further helped us to discover the various methods of

relating the theoretical work to the real world problems, hence establishing the needed solutions

to the problems.

vii

LIST OF FIGURES

Figure 1: Components of a 4-stroke gasoline engine cylinder.....................................................................7

Figure 2: Engine cycle of a 4- stroke gasoline engine.................................................................................8

Figure 3: Engine cycle of a 2-stroke gasoline engine...............................................................................10

Figure 4: operation diesel engine..............................................................................................................12

Figure 5: radial flow turbine.....................................................................................................................16

Figure 6: Turbocharger with twin-entry turbine.......................................................................................18

Figure 7: Water-cooled turbine housings..................................................................................................19

Figure 8: Cutaway view of a turbocharger................................................................................................21

Figure 9: Turbocharger operation.............................................................................................................22

Figure 10: Turbocharger Installed in Engine Bay Side and Front Views..................................................31

Figure 11: Selected Radiator…………………………………………………………………….35

Figure12: Radiator – UndersideS……………………………………………………………….37

Figure 13 Turbocharger Cooling System Layout – Front View……………………………….38

viii

LIST OF TABLES

Table 1: 4 stroke operation for diesel Engine............................................................................................13

Table 2: Data Needed In Calculation..........................................................................................................30

Table 3: Radiator Temperatures................................................................................................................34

Table 4: Radiator Water and Air properties...............................................................................................34

Table 5: Intercooler Temperature............................................................................................................35

Table 6: Intercooler Water........................................................................................................................36

ix

TABLE OF CONTENTSCERTIFICATE............................................................................................................................................ i

DECLARATION......................................................................................................................................... ii

DEDICATION............................................................................................................................................ iii

LIST OF ABBREVIATIONS.....................................................................................................................iv

ACKNOWLEDGEMENT..........................................................................................................................vi

ABSTRACT..............................................................................................................................................vii

LIST OF FIGURES..................................................................................................................................viii

LIST OF TABLES............................................................................................................................................ ix

CHAPTER 1: INTRODUCTION................................................................................................................1

1.1 GENERAL INTRODUCTION..........................................................................................................1

1.1.1.Project back ground....................................................................................................................1

1.1.1.1: MISSION................................................................................................................................1

1.1.1.2: VISION..................................................................................................................................1

1.2: OBJECTIVES..................................................................................................................................1

1.3: Problem statement............................................................................................................................2

1.4: Purpose of study turbocharger for two wheels..................................................................................2

1.5: Main objectives................................................................................................................................3

1.6: Research questions...........................................................................................................................3

1.7: Hypothesis........................................................................................................................................3

1.8: Scope................................................................................................................................................4

1.9: Signification of the study..................................................................................................................4

1.10: Methodology..................................................................................................................................4

CHARPII: LITERRATURE REVIEW..................................................................................................................5

2.1: Background Information...................................................................................................................5

2.1.1: Internal Combustion Engine......................................................................................................5

x

2.1.2: DIESEL ENGINE........................................................................................................................11

2.1.2.1: MIXTURE FORMATION IN DIESEL ENGINES..............................................................11

2.1.2.2: DESIGN OF DIESEL ENGINE...........................................................................................11

2.1.2.3: FEATURES OF A DIESEL ENGENE.................................................................................12

2.2: Operating principle of diesel engine...............................................................................................12

2.3: Definition of turbocharger..............................................................................................................14

2.3.1: Design and Function of a Turbocharger...................................................................................15

2.3.1.1: Turbine.................................................................................................................................15

2.4: Forced Induction.............................................................................................................................19

2.5: Turbo charging versus supercharging.............................................................................................21

2.5.1: operating principle...................................................................................................................22

2.6 Pressure increase / boost...........................................................................................................23

2.7 Boost threshold............................................................................................................................25

2. 8 AIR SPECIFICATION...................................................................................................................26

2.9 IDENTIFY APPROXIMATE PERFORMANCE MATCH............................................................27

CHAPTER 3: METHODOLOGIES..................................................................................................................29

3.1: RESEACH DESIGN......................................................................................................................29

3.2. Research instrument.......................................................................................................................29

3.3. Data Gathering Procedures.. 29

3.4: Data Analysis.................................................................................................................................30

3.5: Limitation of the study...................................................................................................................30

CHAPTER 4: DATA COLLECTION AND ANALYSIS.........................................................................................31

4.1 Fit Check and Installation of the Turbocharger................................................................................31

4.2 Compressor Flow Rate....................................................................................................................32

4.3 Radiator Initial Analysis..................................................................................................................33

xi

4.4 Intercooler Analysis.........................................................................................................................35

4.5 System Installation and Instrumentation..........................................................................................36

CHAPTER 5: CONCLUSIONS AND RECOMMANDATION...............................................................39

5.1 CONCLUSION...............................................................................................................................39

5.2 RECOMMANDATION..................................................................................................................40

REFERENCES..............................................................................................................................................41

xii

CHAPTER 1: INTRODUCTION

1.1 GENERAL INTRODUCTION

1.1.1.Project back ground

1.1.1.1: Mission

To eliminate the main causes of avoidable blindness by the year 2020 by facilitating the

planning, development and implementation of sustainable national eye care programmes based

on the three core strategies of disease control, human resource development and infrastructure

and technology, incorporating the principles of primary health care. This will be achieved by

mobilizing the will and passion for action through advocacy and by mobilizing resources.

1.1.1.2: Vision

A world in which no one is needlessly blind and where those with unavoidable vision loss can

achieve their full potential.

The overall aim is to eliminate the main causes of avoidable blindness and to prevent the

projected doubling of avoidable vision impairment between 1990 and 2020. From the outset, it

has been clear that the goal of eliminating avoidable blindness would best be achieved by

integrating an equitable, sustainable, comprehensive eye-care system into every national health

system. The VISION 2020 initiative is intended to strengthen national health-care systems and

facilitate national capacity-building.

1.2: OBJECTIVES

Increase awareness, within key audiences, of the causes of avoidable blindness and the solutions

to the problem.

Advocate for and secure the necessary resources to increase prevention and treatment activities;

and

Facilitate the planning, development and implementation of national VISION 2020 programmed

in all countries.

1

National programmed have three main elements: cost-effective disease control, human resource

development and infrastructure and technology.

VISION 2020 is built on a foundation of community participation. Overarching issues, such as

equity, quality of services and visual outcomes, are addressed as part of national programmed.

In 2000 the Government had proposed ideas of 2020 vision in purpose of improving Rwandan’s

life such health, kills, technology, science, to eliminate the poverty in Rwandan’s society. After

doing some observations, interview, and Reading about what Rwandan people Needs about their

life and facilities in their works the aim of this dissertation is to highlight the possible challenges

in the exercise of the improvement discussed above in developing the following topic: “study of

turbocharger for two wheels" Whereby the people have been advised to use the car which has

that system and the entrepreneurs to design the cars of that kind.

1.3: Problem statement

Athought the development is growing fast in Rwanda,and the number of populations rising up, it

has been proved that there is a great number of people who are still using the traditional cars, and

these lead on various problems such as:

o Environment destroy

o Health contamination

o Use of the car of low power

o High engine consumption

o High engine temperature

1.4: Purpose of study turbocharger for two wheels

The purpose of this project is to let people know about “turbocharger for two wheels”, it will be

shown them the benefits of using free turbocharger for two wheels.

2

Will also be encouraging them to minimize the use of tradition cars without that system by

showing them the risks that they can occur when the people keep on using the traditional cars.

1.5: Main objectives

The main objective of this work is to encourage people to use free turbocharger which has more

advantages instead of using a tradition cars without that system, which has more disadvantages

as we have seen earlier.

1.6: Research questions

How turbocharger does reduce engine consumption?

How it can destroy environment?

Turbocharger can increase the power of engine? How?

What are the problems provided by the cars without turbocharger for human life?

1.7: Hypothesis

A hypothesis of the study is an anticipated answer to the problem which can be confirmed or

rejected along the study. In our study we will deal with the following hypotheses:

In our country, if there are those people who are still buying and selling the traditional cars and

machines, it is not because it is not easy to get it, or it is they last choice; but it is because they

don’t know about other kind of device they can use (it advantages about life, and power

generated by that device) in our project we will show all important of using cars with

supercharger (turbocharger).

1.8: Scope

The geographical scope of the study will be limited in Kigali city, this due to time and financial

constraint unfavorable to conduct the research in the whole country or whole world. This area is

appropriate to my study, it is easy or the researcher to collect information as it is closer to

researcher. The study will cover the period from when Rwanda adopted the programmer of

protecting the environment.

3

1.9: Signification of the study

Not only that this project will upgrade our Knowledge, but it will also contribute to solve

population and local community basic needs such as:

Saving time

Saving money

Health improvement

And finally save forest and soil.

1.10: Methodology

This project it carry on in study of TURBOCHARGER for two wheels in way for searching a

gap and shall make how it can be resolved and are proposed to do it in KIGALI CITY whereby

willing are to get the information from different books, class documents, internet research, and

other existing project as well as doing interview with people and questioning cur

4

CHARP2: LITERRATURE REVIEW

2.1: Background Information

This section of the paper contains the results of the background research conducted by the team.

These findings include general information about internal combustion engines, forced induction

and turbochargers.

There are two kinds of engines: gasoline engine and diesel engine.

This research is based on Toyota Land cruiser Colorado/Prado with engine (3.0D Turbo).

2.1.1: Internal Combustion Engine

The internal combustion engine is the powerhouse of a variety of machines and equipment

ranging from small lawn equipment to large aircraft or boats. Given the focus of this paper, the

most important machine powered by an internal combustion engine is the automobile. The

engine literally provides the driving force of the car while also directly or indirectly powering

just about every other mechanical and electrical system in the modern automobile. While there

are several types of internal combustion engines that cover the aforementioned large range of

applications, they all basically do the same thing. They all convert the chemical energy stored in

a fuel of some kind into mechanical energy, which can then be converted into electrical energy.

The three most common types of internal combustion are the 4-stroke gasoline engine, the 2-

stroke gasoline engine, and the diesel engine. A brief description of each the common types of

internal combustion engine are provided below.

The 4-stroke gasoline engine is the most frequently used engine in cars and light trucks as well

as in large boats and small aircraft.

While the arrangement and number of the cylinders in an engine tends to vary, the parts that

make up an individual cylinder remain pretty constant. The most significant component is the

piston which is connected to the crankshaft via a connecting rod.

The motions of the piston and crankshaft are always related, with one always forcing the other to

move. The two valves, intake and exhaust, at the top of the cylinder are opened and closed by

separate camshafts that precisely control the timing of each valve’s movement. The spark plug at

the top of the cylinder is powered by the engine battery and activated by the engine computer at

5

the appropriate time. Finally, the entire cylinder is surrounded by coolant channels that run

through the engine block to remove the massive amount of heat generated by the running engine.

6

Figure 1: Components of a 4-stroke gasoline engine cylinder

The four strokes of a 4-stroke gasoline engine, illustrated in Fig. 1, are intake, compression,

power and exhaust. During the intake stroke, the camshaft opens the intake valve as the

crankshaft lowers the piston, which allows the cylinder to be filled with a precise mixture of air

and gasoline. Once the piston reaches the bottom of the cylinder, the camshaft closes the intake

valve. The piston is now at what is known as bottom dead center, and the cylinder is completely

filled with the air/fuel mixture.

7

Figure 2: Engine cycle of a 4- stroke gasoline engine

The compression stroke comes next. With both intake and exhaust valves closed, the crankshaft

raises the piston, compressing the air/fuel mixture. When the piston has been raised to the top of

the cylinder, it is said to be at top dead center. Once the cylinder has reached top dead center, the

air/fuel mixture has been compressed as much as possible.

8

The power stroke is next up. With the piston still at top dead center and both valves closed, the

spark plug fires, igniting the compressed air/fuel mixture. Once ignited, a flame begins to move

through the mixture, causing it to expand downward smoothly. This expansion downward forces

the piston to move down. This means that the piston is rotating to the crankshaft, whereas the

rotation of the crankshaft moves the piston in the other three strokes. The fact that the piston is

driving the crankshaft means that energy is being transferred to the crankshaft. This is how an

internal combustion engine transforms chemical energy in the fuel into mechanical energy. The

power stroke is completed once the expanding gases have forced the piston to bottom dead

center. The final stroke is the exhaust stroke. The camshaft opens the exhaust valve as the

crankshaft raises the piston, which pushes the exhaust gases out of the cylinder. Once the piston

has reached top dead center, all of the exhaust gases have been removed from the cylinder. The

cylinder is now ready to start the cycle over again with another intake stroke. The 2-stroke

gasoline engine accomplishes the same thing as the 4-stroke gasoline engine but with half as

many strokes. Since they can produce a good amount of power for their relatively small size, 2-

stroke gasoline engines are found on a variety of lawn care and recreational equipment like

lawnmowers, chainsaws, snowmobiles and small boat engines. They are generally not used for

larger application because they are less efficient and dirtier than their 4-stroke counterparts.

Aside from having fewer strokes, 2-stroke engines differ from 4-stroke engines in their fuel

mixtures and cylinder components. The two strokes, upstroke and down stroke, of a 2-stroke

9

engine along with the cylinder setup can be seen in

Figure 3: Engine cycle of a 2-stroke gasoline engine.

There are no camshafts or complicated valve trains involved here, meaning the piston basically

has to perform more diverse functions that in 4-stroke engines. Furthermore, special two cycle

oil is mixed in with the gasoline to help lubricate the piston, so the air/fuel mixture in a 2-stroke

engine includes oil. When the piston is at the bottom of the cylinder, the already compressed

air/fuel mixture has moved via the transfer port into the top of the cylinder. On the upstroke, the

piston further compresses the air/fuel mixture, creates a vacuum in the crankcase and uncovers

the intake port. The vacuum opens the intake valve and draws more air/fuel mixture into the

crankcase. The spark plug fires and ignites the mixture, which forces the piston down just like in

the 4-stroke cycle. On the downs stroke, the piston transfers energy to the crankshaft while

compressing the air/fuel mixture in the crankcase and uncovering the exhaust port. As the 8

Piston reaches the bottom of the cylinder; the compressed air/fuel mixture is again forced into

the top of the cylinder via the transfer port, which forces the remaining exhaust out of the

cylinder. The cycle can now begin again. [1]

10

2.1.2: DIESEL ENGINE

2.1.2.1: Mixture Formation In Diesel Engines

In contrast to spark-ignition engines with conventional manifold injection, diesel engines have

interior mixture formation, i.e. the fuel is injected in liquid form at high pressure into the

combustion chamber, where it combusts with the precompressed air.

2.1.2.2: Design of Diesel Engine

The diesel engine, like spark-ignition engine, consists primary of four assemblies and addition

auxiliary installations:

Engine case

Crankshaft drive

Engine timing

Fuel system with the fuel-injection equipment, fuel-supply pump, fuel filter, high-pressure

injection system e.g.

-Common-rail

-Unit-injector system

Auxiliary installations

Engine lubrication, engine cooling, exhaust system, if necessary supercharging system, e.g. with

exhaust gas turbocharger and intercooling, if necessary cold-starting system, preheating system

The diesel engine is used as a fast-running engine with speeds up to approx. 5500 rpm in

passenger cars and light commercial vehicles. It is used as a slow –running engine (speeds up to

approx. 2200rpm) in commercial vehicles.

The diesel engine consumes up to 30% less fuel than spark-ignition engines. Their efficiency can

stretch up to 46%

11

2.1.2.3: Features of a Diesel Engine

Running on diesel or biodiesel fuel

Internal mixture formation

Only air is admitted into the cylinder during the induction stroke. The fuel-air mixture is

formed during the compression stroke by the injection of fuel under high pressure into the

cylinder.

Auto-ignition

Immediately after being injected, the fuel is automatically ignited on the air, which has

been rendered extremely hot by compression. The final compression temperature exceeds

the ignition temperature.

Quality regulation

The naturally aspirated engine is unthrottled, i.e. there is no throttle valve before the

intake ports.

2.2: Operating principle of diesel engine

The four strokes of the power cycle are, as in a spark-ignition engine, induction, compression,

combustion and exhaust. One power cycle takes place in two crankshaft revolution (7200crank

angle).

Figure 4: operation diesel engine

12

Table 1: 4 stroke operation for diesel Engine

1st stroke-induction 2ndstroke-compression 3rdstroke-combustion 4th stroke

exhaust

As the piston moves

down the cylinder, the

increased volume in

the cylinder cause a

pressure differential

pa of -0.1 bars to -0.3

bars compared with

the external pressure.

Air is forced into the

cylinder by the great

external pressure. The

air is admitted

unthrottled because

there is no throttle

valve. In order to

admit as much intake

air as possible into the

cylinder, the inlet

valve opens at up to

250 CA before TDC;

it close only at up to

280 CA after BDC in

order to facilitate a

subsequent flow of

intake air. The air

heats up to 700C to

1000C in the cylinder.

As the piston moves up

the cylinder, the air is

compressed to a 14th to

a 24th of the original

cylinder volume. The

air heats up to 600oc to

900oc in the process.

Because the air cannot

expend at the high

temperature, the final

compression pressure

increase to 30 bars to 55

bars. Engines with

secondary combustion

chambers, such as a

turbulence chamber for

example, must be

compressed to a greater

extent because heat

losses are generated by

the larger combustion

chamber surface. The

inlet and exhaust valves

are closed during the

compression stroke.

Towards the end of the

compression stroke, at

roughly 15oc AC before

TDC to 30oc CA before

TDC, finely atomized

diesel fuel is injected

under high pressure (up

to2050 bar) into the

combustion chamber.

The fuel evaporates in

the hot air and mixes

with the air.

Combustion is initiated

due to the fact that the

temperature of the

compressed air is

higher than the diesel

fuel’s auto-ignition

temperature of 320oc to

380oc. the time

between the start of

injection and the start

of combustion is

known as the ignition

lag. The high

combustion pressure of

up to 160 bar moves

The exhaust

valve opens at

300 to approx.

600 before BDC;

this encourages

the discharge of

the exhaust gases

and relieves the

load on the

crankshaft drive.

The pressure of 4

bar to 6bar still

available at the

end of the power

stroke causes the

exhaust gases

heated up to

5500C to 7500C

to be expelled

from the

cylinder. As the

piston moves up

the cylinder, the

remaining

exhaust gas is

discharged at the

pressure of

13

the piston towards

BDC. Thermal energy

is converted into

mechanical work in the

process.

0.2bar to 0.4bar.

The exhaust

valve closes

slightly before or

after TDC. The

heat losses are

lower than in

spark – ignition

engine due to the

lower exhaust –

gas temperatures

(greater

efficiency).

[2]

2.3: Definition of turbocharger

The purpose of this paper is to summarize the basic principles that are used in the study of

turbocharger for two wheels.

The turbocharger system is applied in the heavy vehicles and the vehicle which is used in the

hills circulation and certain machines for example agriculture machines etc….

Forced induction dates from the late 19th century, when Gottlieb Daimler patented the technique

of using a gear-driven pump to force air into an internal combustion engine in 1885. The

turbocharger was invented by Swiss engineer Alfred Buchan (1879-1959), the head of diesel

engine research at Begrudge Seltzer engine manufacturing company in Winter, who received a

patent in 1905 for using a compressor driven by exhaust gasses to force air into a diesel engine to

increase power output but it took another 20 years for the idea to come to fruition. During World

War I French engineer Augusta Rameau fitted turbochargers to Renault engines powering

various French fighters with some success. In 1918, General Electric engineer Sanford

Alexander Moss attached a turbo to a aircraft engine.

14

The engine was tested at Pikes Peak in Colorado at 14,000 ft (4,300 m) to demonstrate that it

could eliminate the power loss usually experienced in internal combustion engines as a result of

reduced air pressure and density at high altitude. General Electric called the system turbo

supercharging. At the time, all forced induction devices were known as superchargers, however

more recently the term "supercharger" is usually applied to only mechanically-driven forced

induction devices.

Turbochargers were first used in production aircraft engines such as the Napier Lioness in the

1920s, although they were less common than engine-driven centrifugal superchargers. Ships and

locomotives equipped with turbocharged Diesel engines began appearing in the 1920s.

Turbochargers were also used in aviation, most widely used by the United States, which led the

world in the technology due to General Electric's early start During World War II, notable

examples of use aircraft with turbochargers include the B-17 Flying Fortress, B-24 Liberator, P-

38 Lightning and P-47 Thunderbolt. The technology was also used in experimental fittings by a

number of other manufacturers, notably a variety of Fouke Wolf Few 190 models, but the need

for advanced high-temperature metals in the turbine kept them out of widespread use.

Turbocharger for two wheels contain main

2.3.1: Design and Function of a Turbocharger

2.3.1.1: Turbine

Design and function

The turbocharger turbine, which consists of a turbine wheel and turbine housing, converts the

engine exhausts gas into mechanical energy to drive the compressor.

The gas, which is restricted by the turbine's flow cross-sectional area, results in a pressure and

temperature drop between the inlet and outlet. This pressure drop is converted by the turbine into

kinetic energy to drive the turbine wheel.

There are two main turbine types: axial and radial flow. In the axial-flow type, flow through the

wheel is only in the axial direction. In radial-flow turbines, gas inflow is centripetal, i.e. in a

radial direction from the outside in, and gas outflow in an axial direction.

15

Up to a wheel diameter of about 160 mm, only radial-flow turbines are used. This corresponds to

an engine power of approximately 1000 kW per turbocharger. From 300 mm onwards, only

axial-flow turbines are used. Between these two values, both variants are possible.

As the radial-flow turbine is the most popular type for automotive applications, the following

description is limited to the design and function of this turbine type.

In the volume of such radial or centripetal turbines, exhaust gas pressure is converted into kinetic

energy and the exhaust gas at the wheel circumference is directed at constant velocity to the

turbine wheel. Energy transfer from kinetic energy into shaft power takes place in the turbine

wheel, which is designed so that nearly all the kinetic energy is converted by the time the gas

reaches the wheel outlet.

Figure 5: radial flow turbine

The turbine performance increases as the pressure drop between the inlet and outlet increases,

i.e. when more exhaust gas is dammed upstream of the turbine as a result of a higher engine

speed, or in the case of an exhaust gas temperature rise due to higher exhaust gas energy.

16

The turbine's characteristic behavior is determined by the specific flow cross-section, the throat

cross-section, in the transition area of the inlet channel to the volute. By reducing this throat

cross-section, more exhaust gas is dammed upstream of the turbine and the turbine performance

increases as a result of the higher pressure ratio. A smaller flow cross-section therefore results in

higher boost pressures.

The turbine's flow cross-sectional area can be easily varied by changing the turbine housing.

Besides the turbine housing flow cross-sectional area, the exit area at the wheel inlet also

influences the turbine's mass flow capacity. The machining of a turbine wheel cast contour

allows the cross-sectional area and, therefore, the boost pressure, to be adjusted. A contour

enlargement results in a larger flow cross-sectional area of the turbine.Turbines with variable

turbine geometry change the flow cross-section between volute channel and wheel inlet. The exit

area to the turbine wheel is changed by variable guide vanes or a variable sliding ring covering a

part of the cross-section.

In practice, the operating characteristics of exhaust gas turbocharger turbines are described by

maps showing the flow parameters plotted against the turbine pressure ratio. The turbine map

shows the mass flow curves and the turbine efficiency for various speeds. To simplify the map,

the mass flow curves, as well as the efficiency, can be shown by a mean curve

For high overall turbocharger efficiency, the co-ordination of compressor and turbine wheel

diameters is of vital importance.

The position of the operating point on the compressor map determines the turbocharger speed.

The turbine wheel diameter has to be such that the turbine efficiency is maximized in this

operating range.

17

Figure 6: Turbocharger with twin-entry turbine

The turbine is rarely subjected to constant exhaust pressure. In pulse turbocharged commercial

diesel engines, twin-entry turbines allow exhaust gas pulsations to be optimized, because a

higher turbine pressure ratio is reached in a shorter time. Thus, through the increasing pressure

ratio, the efficiency rises, improving the all-important time interval when a high, more efficient

mass flow is passing through the turbine. As a result of this improved exhaust gas energy

utilization, the engine's boost pressure characteristics and, hence, torque behavior is improved,

particularly at low engine speeds.

To prevent the various cylinders from interfering with each other during the charge exchange

cycles, three cylinders are connected into one exhaust gas manifold. Twin-entry turbines then

allow the exhaust gas flow to be fed separately through the turbine.

18

Figure 7: Water-cooled turbine housings

Turbocharger with water-cooled turbine housing for marine applications

Safety aspects also have to be taken into account in turbocharger design. In ship engine rooms,

for instance, hot surfaces have to be avoided because of fire risks. Therefore, water-cooled

turbocharger turbine housings or housings coated with insulating material are used for marine

applications.

2.4: Forced Induction

In automotive applications, forced induction quite literally means to force air into the engine.

Under standard atmospheric conditions, the engine will naturally consume a volume of air equal

to its engine displacement each time it completes its 4-stroke cycle and is said to be naturally

aspirated. When some form of forced induction is added, the engine will be forced to consume a

volume of air greater than its engine displacement each time it completes its 4-stroke cycle.

While this may seem trivial, it is very significant and can result in large power gains for the

engine.

The method by which a 4-stroke gasoline engine converts chemical energy into mechanical

energy . It should be stated plainly that the chemical energy is found entirely within the fuel, and

thus the power generated by the engine is directly related to how much fuel is in the cylinders

during the power stroke. However, simply flooding the cylinder with gasoline will not result in

more power but will manage to seriously damage the engine. Section2.2.1 mentions that the

engine is designed to operate at a specific air/fuel ratio (AFR).

19

What this means is that for every particle of fuel there needs to be a corresponding number of air

molecules. If this ratio is disturbed, the engine will run lean (too little fuel) or rich (too much

fuel), either one of which is bad for engine. The engine control unit (ECU) monitors the airflow

into the engine and adjusts fuel injection accordingly to maintain a proper AFR. Thus the only 12

way to really get more fuel into the cylinders, and enjoy the added power, is to increase the

airflow into the engine, hence the importance of forced induction. Forced induction systems

make use of a compressor to force more air into the cylinders of the engine. In order to maintain

a proper AFR, the ECU tells the fuel injectors to spray more fuel into the cylinders, resulting in

more power. The compressor is able to force more air into the cylinders by increasing the

pressure of the ambient air before it enters the intake ports. With a constant cylinder volume, a

lot more air can fit into the cylinder at 20psi than at atmospheric pressure, 14.7psi. An

unavoidable thermodynamic result of increasing the air’s pressure is to also increase its

temperature. The compressor thus raises both the pressure and the temperature of the air. The

two most common types of forced induction are turbo charging and supercharging.

Turbochargers and superchargers both use compressors to raise the pressure of the intake air as

described above. These devices differ in the way by which they power the compressor. A

turbocharger uses exhaust gases expelled from the cylinders to spin a turbine, which in turn

powers the compressor. Figure 8.Shows a cutaway view of a typical turbocharger. The black

housing with red highlights on the left is the turbine. The gray housing with blue highlights on

the right is the compressor. The yellow and green section in the middle contains the connecting

20

shaft between the turbine and compressor with its bearings.

Figure 8: Cutaway view of a turbocharger

2.5: Turbo charging versus supercharging

Main article: Supercharger

In contrast to turbochargers, superchargers are not powered by exhaust gases but driven by the

engine mechanically; Belts, chains, shafts, and gears are common methods of powering a

supercharger. A supercharger places a mechanical load on the engine to drive, For example, on

the single-stage single-speed supercharged Rolls-Royce Merlin engine, the supercharger uses up

about 150 horsepower (110 kW). Yet the benefits outweigh the costs: For that 150 hp (110 kW),

the engine generates an additional 400 horsepower, a net gain of 250 hp (190 kW).

This is where the principal disadvantage of a supercharger becomes apparent: the internal

hardware of the engine must withstand the net power output of the engine plus the 150

horsepower to drive the supercharger.

21

In comparison, a turbocharger does not place a direct mechanical load on the engine; it is more

efficient because it uses kinetic energy of the exhaust gas to drive the compressor. In contrast to

supercharging, the principal disadvantages of turbo charging are back-pressure, heat soak of the

intake air and the inefficiencies of the turbine versus direct-drive.

A combination of an exhaust-driven turbocharger and an engine-driven supercharger can

mitigate the weaknesses of the other. This technique is called twin charging

2.5.1: Operating Principle

Figure 9: Turbocharger operation

In most piston engines, intake gases are "pulled" into the engine by the downward stroke of the

pits (which creates a low-pressure area), similar to drawing liquid using a syringe. The amount of

air which is actually inhaled, compared with the theoretical amount if the engine could maintain

atmospheric pressure, is called volumetric efficiency the object of a turbocharger is to improve

an engine's volumetric efficiency by increasing density of the intake gas (usually air).

The turbocharger's compressor draws in ambient air and compresses it before it enters into the

intake manifold at increased pressure, this results in a greater mass of air entering the cylinders

on each intake stroke. The power needed to spin the centrifugal compressor is derived from the

kinetic energy of the engine's exhaust gases.

22

A turbocharger may also be used to increase fuel efficiency without increasing power. This is

achieved by recovering waste energy in the exhaust and feeding it back into the engine intake.

By using this otherwise wasted energy to increase the mass of air, it becomes easier to ensure

that all fuel is burned before being vented at the start of the exhaust stage. The increased

temperature from the higher pressure gives a higher efficiency.

The control of turbochargers is very complex and has changed dramatically over the 100-plus

years of its use. Modern turbochargers can use waste gates, blow-off valves and variable

geometry, as discussed in later sections.

The reduced density of intake air is often compounded by the loss of atmospheric density seen

with elevated altitudes. Thus, a natural use of the turbocharger is with aircraft engines. As an

aircraft climbs to higher altitudes, the pressure of the surrounding air quickly falls off. At 5,486

meters (17,999 ft), the air is at half the pressure of sea level, which means that the engine will

produce less than half-power at this altitude.

2.6 Pressure increase / boost

This unreferenced section requires citations to ensure verifiability.

In automotive applications, "boost" refers to the amount that intake manifold pressure that

exceeds atmospheric pressure. This is representative of the extra air pressure that is achieved

over what would be achieved without the forced induction. The level of boost may be shown on

a pressure gauge, usually in bar, psi or possibly kPa.

In aircraft engines turbo charging is commonly used to maintain manifold pressure as altitude

increases (i.e. compensate for lower density air at higher altitudes).

Since atmospheric pressure reduces as the aircraft climbs, power drops as a function of altitude

in normally aspirated engines. Systems that use a turbocharger to maintain an engine's sea-level

power output are called turbo-normalized systems. Generally, a turbo-normalized system will

attempt to maintain a manifold pressure of 29.5 inches of mercury (100 kPa).

23

In all turbocharger applications, boost pressure is limited to keep the entire engine system,

including the turbo, inside its thermal and mechanical design operating range. Over-boosting an

engine frequently causes damage to the engine in a variety of ways including pre-ignition,

overheating, and over-stressing the engine's internal hardware.

For example, to avoid engine knocking (aqua pre-ignition or detonation) and the related physical

damage to the engine, the intake manifold pressure must not get too high, thus the pressure at the

intake manifold of the engine must be controlled by some means. Opening the waste gate allows

the energy for the turbine to bypass it and pass directly to the exhaust pipe, thus reducing boost

pressure. The waste gate can be either controlled manually (frequently seen in aircraft) or by an

actuator (in automotive applications, it is often controlled by the Engine Control Unit).Turbo lag

Turbocharger applications can be categorized according to those which require changes in output

power (such as automotive) and those which do not (such as marine, aircraft, commercial

automotive, industrial, locomotives). While important to varying degrees, turbo lag is most

problematic when rapid changes in power output are required.

Turbo lag is the time required to change power output in response to a throttle change. For

example, this is noticed as a hesitation or slowed throttle response when accelerating from idle as

compared to a naturally aspirated engine. This is due to the time needed for the exhaust system

and turbocharger to generate the required boost. Inertia, friction, and compressor load are the

primary contributors to turbo lag. Superchargers do not suffer this problem, because the turbine

is eliminated due to the compressor being directly powered by the engine.

Lag can be reduced in a number of ways:

Lowering the rotational inertia of the turbocharger; for example by using lighter, lower

radius parts to allow the spool-up to happen more quickly. Ceramic turbines are of

benefit in this regard and or billet compressor wheel.

Changing the aspect ratio of the turbine.

increasing the upper-deck air pressure (compressor discharge) and improving the waste

gate response

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reducing bearing frictional losses (such as by using a foil bearing rather than a

conventional oil bearing)

Using variable-nozzle turbochargers (discussed below).

Decreasing the volume of the upper-deck piping.

Using multiple turbo sequentially or in parallel.

Using an Antilog system.

2.7: Boost threshold

Lag is not to be confused with the boost threshold. The boost threshold of a turbo system

describes the lower bound of the region within which the compressor will operate. Below a

certain rate of flow, a compressor will not produce significant boost. This has the effect of

limiting boost at particular rpm regardless of exhaust gas pressure. Newer turbocharger and

engine developments have caused boost thresholds to steadily decline.

Electrical boosting ("E-boosting") is a new technology under development; it uses an electric

motor to bring the turbo up to operating speed quicker than is possible using exhaust gases are

available. An alternative to e-boosting is to completely separate the turbine and compressor into

a turbine-generator and electric-compressor as in the hybrid turbocharger. This allows the

compressor speed to become independent to that of the turbine. A similar system utilizing a

hydraulic drive system and over speed clutch arrangement was fitted in 1981 to accelerate the

turbocharger.

Turbochargers start producing boost only when a certain amount of kinetic energy (e.g.

momentum) is present in the exhaust gasses. Without adequate j exhaust gas flow to spin the

turbine blades, the turbo cannot produce the necessary force needed to compress the air going

into the engine. The boost threshold is determined by the engine displacement, engine rpm,

throttle opening, and the size of the turbo. The operating speed (rpm) at which there is enough

exhaust gas momentum to compress the air going into the engine is called the "boost threshold

rpm". Reducing the "boost threshold rpm" can improve throttle response.

25

2. 8: AIR SPECIFICATION

The air specification dictates the combustion engines requirement for airflow rate as well as air

and exhaust pressure. This specification will vary for different makes and models of combustion

engines. Even for multiple, same model, natural gas combustion engines the air specification can

vary depending on;

1) The local regulatory emission requirements,

2) Style of aftermarket fuel injection and other associated equipment implemented,

3) Ambient conditions the turbocharger will be operating within, and

4) The air specification authors’ method of calculating the required airflow rate and density

needed to meet desired engine performance. This document typically includes, at a minimum, the

following parameters for each design point the turbochargers required to operate at:

• Barometric Pressure

• Ambient Temperature

• Intake Air Filtration Pressure Drop

• Compressor Discharge Pressure

• Turbine Inlet Pressure

• Turbine Inlet Temperature

• Turbine Discharge Pressure

• Air Mass Flow Rate

• Exhaust Mass Flow Rate

It is worth noting that turbine inlet pressure is listed with a footnote identifying that its value

within the air specification should appropriately represent the condition most difficult for the

turbocharger to achieve. Elaborating on this, a pressure drop across the system from turbocharger

compressor discharge to turbocharger turbine inlet exists. In essence, this pressure drop

represents the systems’ (combustion engine, inter-cooler, associated manifold piping, and

applicable after treatment) inability to conserve the turbocharger compressor discharge pressure.

The turbine converts static pressure to dynamic head allowing it to extract kinetic energy from

the exhaust gas. With mass flow being conserved the pressure drop across the previously

26

described system represents, in a very general sense, the energy available gradient across the

power cylinder volume.

This pressure gradient enhances the displacement and or entrainment of

Exhaust gasses. This action increases the mass of fresh air available for combustion during the

following power stroke while also reducing cylinder operating temperatures. The accuracy of the

air specification has significant, Importance for multiple reasons. First, it is possible to write the

air specification in a manner, which reflects an extreme or impossible energy balance requiring

the turbine to produce an unreasonable amount of energy. This of course, an incorrect practice,

and typically a byproduct of the air specification writer attempting to use the turbocharger in a

manner beyond which it was intended. Second, if the air specification does not closely

approximate how the engine will react to being turbocharged, then expected on-engine

performance will not be achieved and may require a few iterations at great time and financial

expense to identify combustion air flow and density requirements.

Conduction of heat: it is the energy transfer that takes place at molecular level. Conduction is

the transfer of energy from the more energetic molecules of a substance to the adjacent less

energetic molecules as a result of interaction between the molecules.

Fourier’s law conduction: the empirical law of conduction based on experimental result is

named after the French physicist Joseph Fourier. The law states that the rate of heat flow by

conduction in any medium in any direction is proportional to the area normal to the direction of

heat flow and also proportional to the temperature gradient in that direction.

2.9: IDENTIFY APPROXIMATE PERFORMANCE MATCH

Cursory review of the air specification leads to identifying the most suitable frame size or family

of turbochargers, which will operate with reasonable efficiencies while meeting the specified

airflow rate and air density requirement. Correcting existing compressor operating maps to

ambient temperature and barometric pressure dictated by the air specification while overlaying

the desired design points identifies the best-suited family of turbocharger compressor for the

application. This comparison immediately identifies compressor surge margin, choke margin,

27

basic operational stability, isentropic compressor efficiency, and overall capacity of the

turbocharger compressor to achieve desired flow characteristics. [3]

Benefits

Decrease exhaust emissions, smoke and noise

Increase output power

Maintain nearly constant power at high altitudes

Better fuel economy

Main advantages

Improved engine power

Improved acceleration ability

Improved fuel consumption

Fast warm-up

Ease to meet emission regulation

Hi- Speed Hi-Load: Exhaust gas has a large contact area; turbo response and speed

are increased. (Max. power up10-15%)

Low-Speed Low-Load: Kinematics energy is maximized due to the narrow flow

section area. (Max. torque is up 5-15)

Summary of turbocharger

Turbine-Driven compressor

Propelled by Engine Exhaust Gas

Increases Air Flow and Density

Creates Stronger “Explosion” [4]

28

CHAPTER 3: METHODOLOGIES

3.1: RESEACH DESIGN

The Methodology Is Constituted By different systems which are necessary for getting the

information about work, the researcher must use whatever kind of manner to get news from

various people in difference areas where the researcher has a optimism to found it in order to

reach to the desired solution(conclusion).

32. Research instrument

Research will use deferent instruments such as;

Observations checklist.

Some document on the Internet

3.3. Data Gathering Procedures

The theory and general methodology was developed based upon known temperatures, boost

pressure, and driving conditions. Heat needs to be removed from the compressed air before it

enters the engine. Heat needs to be removed from the water after it exits the intercooler. Basic

heat exchanger analysis was used to analyze both the intercooler and radiator. The steps followed

to complete the analysis are below:

1) Analyze the compressor flow rate

2) Analyze the water-air radiator and analyze the intercooler

3) Test

4) Repeat analysis with test data

29

3.4: Data Analysis

Table 2: Data Needed In Calculation

Data use Amounts Values used

Area (0.7*0.4)m2 means w*L 0.28m2

Thermal conductivity k 100w/m2k 100w/m2k

Temperature(water) for

radiator

85-140OC inlet

40-600C Outlet

95OC

Intercooler Temperature (Air) 50-90 inlet 70OC

Temperature (h) 25-200w/m2k 100w/m2k

Thickness 0.07m

This indication is for Rwanda weather conditions but in our research the inlet temperature of water is 950C and 70OC for air.

L= Where length

W= width

Data will be analyzed for the research subject will check data from books and internet seeing

what other researchers have found.

30

3.5: Limitation of the study

During the period of the study, the research will look forward to Rwanda; the books; because

there are many references in extra-country and technology developed rapidly. While the

invention has been described with respect to obtain specific embodiments, it will be appreciated

that many modifications changes may be made by those skilled in the art without departing from

the spirit of invention. It is intended, therefore by appended claims to cover all such modification

and changes as fall within the true spirit and limitation of the inventions.

CHAPTER 4: DATA COLLECTION AND ANALYSIS

4.1 Fit Check and Installation of the Turbocharger

The turbocharger was installed with minimal modifications to the vehicle. The exhaust manifold

was modified to bolt the turbocharger to the engine and a flange on the turbocharger was

modified to allow proper orientation of the oil inlet/outlet and the air inlet/outlets. None of the

modifications affected the function of the turbocharger. Figure 10 shows the turbocharger

installed on the passenger side of the engine. The silver half of the turbocharger is the

compressor and the rust colored portion is the turbine.

31

Test drives with the turbocharger installed (and no intercooling system) showed reasonable boost

pressures and engine inlet air temperatures exceeding 168°c. This information was used to better

focus the heat exchanger analysis to be described in the next section. [5]

32

Figure 10: Turbocharger Installed in Engine Bay Side and Front Views

4.2 Compressor Flow Rate

To determine the compressor flow rate there are several characteristics of the engine that must be

known. The cubic inches of displacement (CID), revolutions per minute for turbocharging

(RPM) and the engine volumetric efficiency (VE) must be known. CID and VE are engine

specifications. RPM depends on the vehicle and the scenario (situation) in which turbocharging

is being used. To calculate the airflow rate in cubic feet per minute (CFM), the following

equation was used,

AIRFLOW= (1)

Where 3,456 is a conversion factor from cubic inches to cubic feet and includes a ½ parameter

needed for four-stroke engines which only exhaust every other revolution. This airflow rate is

based upon atmospheric pressure; it does not consider the boost pressure. The goal (aim) is to

increase boost pressure to 18psi, so the airflow rate is needed at 18psi. For this boost pressure,

Pb, a pressure ratio (PR) is needed,

PR= (2)

To calculate the new flow rate at the given boost pressure of 18psi the flow rate is calculated

using the pressure ratio,

Corrected CFM=PR*oldcfm (3)

The airflow rate for the compressor wass calculated first to determine if the compressor is of

suitable size for the system. The mass flow rate of the air was calculated from the compressor

flow rate given in Equation (1), Equation (2), and Equation (3).

33

Equation (1) uses Cubic Inch displacement (CID), 395, revolutions per minute (RPM) at which

turbo charging will occur, 2000, and the volumetric efficiency (VE), 80%. These values are part

of the engine specifications. These values in Equation (1) give a volumetric flow rate of,

Q1 = VA =

This is the nominal airflow rate of the engine at atmospheric pressure. Airflow at the desired

boost pressure of 18 psi was calculated. The pressure ratio of Equation (2) was calculated,

PR= = 2.22

Given the new pressure ratio, a new airflow rate was calculated and from that the mass flow rate

was calculated,

Q=183*PR=407cfm =0.192m3/s

ma=ρ*Q=0.192m3/s* 1.1kg/m3=0.21kg/s

Qα A(Dt/dx) eq(4)

Heat transfer =kA(dT/dx) in watt eq(5)

A: Area

dT/dx: temperature gradient

k: thermal conductivity

Thermal diffusivity: this is a property which is very helpful in analyzing transient heat

conduction problem and is normally denoted by the symbol α. It is defined as follows.

Α=heat conducted/heat stored per unit volume =k/ρCp

Q=KA(Dt/dx)=100*0.7*0.4(120-80)/0.07=16000w

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4.3 Radiator Initial Analysis

Given the operating environment an ambient air temperature of 27°C, then the water flowing

through the radiator will not be exactly 27°C, but 20 to 120 degrees. Therefore a water outlet

temperature of 48°F was chosen as an initial point. As these choices indicate there are many

assumptions being made about the turbocharger system and the fluids within it. Table 2 shows

the radiator inlet and outlet temperatures in Celsius. The key assumptions are listed below.

Table 3: Radiator Temperatures

Water(oc) Air(oc)

Inlet 95 27

Outlet ? 42

The first step was to find all of the properties for air and water. Since the temperature of water

and air changes across the heat exchanger, the fluid properties were found at the average

temperature for each of the fluids.

Heat Transfer=KA (Dt /dx) Tf= Outlet Temperature Of Water

16000=100*0.28(368OK-Tf)/0.07m

16000*0.07=10304-28TF

1120-10304=-28Tf

-9184=-28Tf

Tf=328OK

TF=550C

The subscript “w” in this and all subsequent calculations is water, “A” is air. Since an air outlet

temperature t2, The properties for water and air were found at their average temperatures, using

published tables and calculators (ref. Table 3)

Table 4: Radiator Water and Air properties

Density ρ (kg/m2) Specific heat

Cp(J/kgK)

35

Water 972 4.198*103

Air 1.1 1.009*103

Figure 11: Selected Radiator

4.4 Intercooler Analysis

Intercooler analysis followed radiator analysis since a water inlet temperature was previously

calculated. The same calculations used for the radiator were used for the intercooler.

Inlet and outlet temperatures for water (the cooler fluid) and air (the warmer fluid) are in Table 5.

The outlet water temperature, also the inlet radiator temperature, is C. Initial runs with the

turbocharger (no intercooler) showed inlet air temperatures in excess of 110°C,

However the inlet air temperature (IAT) should not exceed 82°C. The assumed temperatures are

shown in Table 5

Table 5: Intercooler Temperature

Water(OC) Air(OC)

INLET 55 70

OUTLET 90 ?

The first step was to find all of the properties for air and water. For this the average temperature

was taken for both water and air.

36

Q2=hA (Dt /dx) h=convective heat transfer coefficient

For forced gas = from 25-200w/m2k

In this case is 100w/m2k

Q2 =100*0.28(90-50)/0.07

=16000w

16000=100*0.28(70-To)/0.07 To= outlet Temperature of Air

1120=1960-28To

1120-1960=-28To

-840=-28To

To=30OC

The properties for water and air were found at these temperatures, using tables and calculators

and shown in Table 6 below.

Table6: Intercooler Water

Density ρ(Kg/m3) Specific Heat

CP(J/kgc)

WATER 1000 4.18*103

AIR 1.1 1.01*103

4.5 System Installation and Instrumentation

The vehicle owner installed the components into the engine bay (inlet). The pictures below show

the installation locations. The turbocharger had remained installed from the trial (check) fit . The

Intercooler was installed on the top right of the engine block. The air hoses were routed from the

compressor on the top left side of the engine block to the intercooler on the top right in figure.

The radiator was mounted to the inside of the front bumper, where holes already existed for

routing air. The water pump was mounted in the left front corner of the engine compartment.

37

Figure12: Radiator – UndersideS

38

Figure 13 Turbocharger Cooling System Layout – Front View

Measured temperatures were needed to verify the operation and sizing of the system.

Thermocouples and hand held data loggers were purchased.

The thermocouples were installed into the system at the starred locations shown in Figure 15. In

addition, the vehicle owner had a thermocouple measuring exhaust gas temperatures from the

previous turbocharger. The four thermocouples giving the inlet and outlet temperatures needed

for calculations were fully inserted into the water and air lines. On the air lines, the

thermocouples were pushed in under joints and the joint sealed again. On the water lines, T-

fittings were installed and the thermocouples inserted into the T-fitting. The T-fitting was then

sealed with silicone to prevent water leakage. However, the cloth coating on the thermocouples

absorbed the water and capillary action caused small leaks to occur.

39

Figure 14: Thermocouple locations

CHAPTER 5: CONCLUSIONS AND RECOMMANDATION

5.1 CONCLUSION

The objective of this project was to analyze and install a turbocharger system in Toyota Land

cruiser Colorado/Prado with engine (3.0D Turbo). The turbocharger was selected by the vehicle

owner. The cooling system for the vehicle was selected based on theoretical heat transfer

40

calculations, budget, and available engine bay space. The intercooler and radiator selected

proved to be of proper size for the given conditions. It is possible and practical to use heat

transfer calculations when sizing a turbocharger cooling system. However, one must take into

consideration the operational environment and flow characteristics of the system in order to

make an informed decision on which system to install.

5.2 RECOMMANDATION

The following are a series of recommendations agreed upon by team.

Purchase several pressure and temperature sensors and install them on the turbocharged

engine system once it is operational. Use these sensors to acquire pressure and temperature

data at several points in the turbocharged system. These points should include but are not

limited to before and after the compressor and after the intercooler.

Once the turbocharged system is operational, put it on the engine dynamometer and test it for

airflow, horsepower and torque data over the entire rev range.

Use the airflow data from the turbocharged engine to determine at what RPM the restrictor

chokes and how much airflow it actually permits at that point.

Find a better sized turbocharger for the restricted engine by using the acquired data to better

size the compressor and turbine.

Find a turbocharger that does not have an integral wastegate.

Find a turbocharger that has its oil inlet and outlet on opposite faces of the bearings section

rather than side by side on the same face.

The chassis should be much bigger, particularly the area for the exhaust manifold.

The turbocharger should be placed as high as possible in the chassis to facilitate a gravity

drain oil system, even higher than it currently is would be advisable.

The intake plumbing to the compressor from the restrictor should be in a straight line with no

bends or cross section changes.

The size of the opening above the driver’s seat should be increased to provide sufficient

space to duct the intercooler such that it receives enough ambient airflow.

REFERENCES

41

[1] (Retrieved from http://cache.eb.com/eb/image?id=24075&rendTypeId=4 on April 14, 2008)

[2] Nunn R. H., Intermediate Fluid Mechanics, HemispherePublishing Corporation, New York, 1989

[3] Modern Technology

[4] CFX-TASCflow, Theory Documentation – Version 2.12, Advanced Scientific Computing Ltd, 2002

42

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