Turbo Engine

8/11/2019 Turbo Engine

1/19

Turbo Engines

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Technical

Paper PresentationOn

TURBO ENGINE

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2/19

Turbo Engines

ABSTRA3T

Internal combustion engines are "breathing" engines. That is to say, they draw

in air and fuel for energy. This energy is realized as power when the air-fuel mixture is

ignited. Afterward, the waste created by the combustion is expelled. All of this is

typically accomplished in four stroes of the pistons. The greater emphasis on fuel

economy, engine responsi!eness, and emissions control has dri!en the #$I#%&

towards the de!elopment of turbochargers that ser!e distinct commercial diesel

applications, along with reduction in #'x emmitions.

The basic principal behind turbocharging is fairly simple, but the real thing

behind it is not as simple as it loos. A turbocharger is a !ery complex piece of

machinery. #ot only must the components within the turbocharger itself be precisely

coordinated, but the turbocharger and the engine it ser!ices must also be exactly

matched.

S.S.G.M.C.E., Shegaon (


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Turbo Engines

3ONTENTS

+ Introduction 5+

& Turbo En.ine 5&

( >o= turbo System =or#s 5'

' Basic Terminolo.ies 5:

8 0esi.n 3onsiderations 5)

: Optional Turbo ?eatures 5,

@ Superiority O1 Turbo En.ines +&

) Ad$anta.es +(

, Implementation +8 +5 3onclusion +:

++ Re1erences +:

S.S.G.M.C.E., Shegaon )


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Turbo Engines

forced induction approach has the ad!antage that the intae pressure may be regulated

according to the engine speed, thus pro!iding power from extra capacity at high

speed, but without wasting fuel at lower speeds.

The ad!anced features a turbo engine has which naturally aspirated engines

don5t to ? pounds per s6uare

inch 3psi4. &ince normal atmospheric pressure is 1;.@ psi at sea le!el, you can see that

you are getting about B percent more air into the engine. Therefore, you would

expect to get B percent more power. Its not perfectly efficient, so you might get a

(54 to '54percent impro$ementinstead.

Turbochargers are a type of forced induction system. They compress the air

flowing into the engine . The ad!antage of compressing the air is that it lets the

engine s6ueeze more air into a cylinder, and more air means that more fuel can beadded. Therefore, you get more power from each explosion in each cylinder. A

S.S.G.M.C.E., Shegaon
http://en.wikipedia.org/wiki/Exhausthttp://en.wikipedia.org/wiki/Superchargerhttp://en.wikipedia.org/wiki/Exhausthttp://en.wikipedia.org/wiki/Supercharger


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Turbo Engines

turbocharged engine produces more power o!erall than the same engine without the

charging. This can significantly impro!e the power-to-weight ratio for the engine.

In order to achie!e this boost, the turbocharger uses the exhaust flow from the

engine to spin a turbine, which in turn spins an air pump. The turbine in the

turbocharger spins at speeds of up to 1B,BBB rotations per minute 3rpm4 -- thats

about )B times faster than most car engines can go. And since it is hooed up to the

exhaust, the temperatures in the turbine are also !ery high.

Types o1 turbochar.ers;

!NT 6!ariable Nole Turbine Turbochar.er7

$enerates a higher air density at low engine speeds, allowing a greater inputof fuel for the same air-fuel ratio, increasing power while maing engines more fuel-

efficient and cleaner burning. This technology impro!es low-speed dri!eability and

high-speed fuel economy.

Multi$ane !ariable Geometry Turbochar.er =ith Rotary Electric Actuator

mploys a mobile multi!ane system composed of a number of !anes that

pi!ot on their axis to modify the cross section. An electronically controlled rotary

electric actuator helps to channel exhaust gas to the turbine wheel, enabling moreprecise control of boost pressure o!er the engine5s entire load and speed range. The

result is impro!ed tor6ue, superior fuel economy and compatibility with on-board

diagnostics systems.

Slide$ane Turbochar.er

C#T &lide!ane models employ a mobile nozzle piston system to modify the

cross section and offer :ulti!aneD !ariable technology in a simpler, more cost-

effecti!e pacage on applications in the (.B- to (.-liter range.

Intercooler ;

An intercoolers primary function is to cool the charge of air after it has been

heated due to boosting and the heat that is produced by turbo before sending the air

into the engine .as the air is cooled, it becomes denser , and denser air maes for

better combustion and more power.

In order to increase the power of the engine, the goal is to get more air

molecules into the cylinder, not necessarily more air pressure. Additionally, the

S.S.G.M.C.E., Shegaon >


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Turbo Engines

denser, cooler air helps increase the total amount of boost possible without causing

engine nocing.Air to air intercoolers need to be mounted so as to maximize air

flow and promote efficient cooling. :ost cars such as the &aab3except the &ubaru

E%F based G-(F Aero4, :itsubishi 0ancer !olution, Colswagen and Audi use

front mounted intercooler3s4 37:I=4 mounted !ertically near the front bumper, in line

with the cars radiator.

( >O A TURBO S-STEM ORCS;

If we want our small engine to perform lie a big engine, or simply mae our

bigger engine produce more power, our ultimate obHecti!e is to draw more air into the

cylinder. y installing a turbocharger, the power and performance of an engine can be

dramatically increased.&o how does a turbocharger get more air into the engine/ 0et

us first loo at the schematic belowo= a turbochar.er is plumbed in a car

The exhaust from the cylinders passes through the turbine blades, causing

the turbine to spin. The more exhaust that goes through the blades, the faster they

spin. 'n the other end ,of the shaft

S.S.G.M.C.E., Shegaon @
http://en.wikipedia.org/wiki/Engine_knockinghttp://en.wikipedia.org/wiki/Saab_Automobilehttp://en.wikipedia.org/wiki/Mitsubishi_Lancer_Evolutionhttp://en.wikipedia.org/wiki/Volkswagenhttp://en.wikipedia.org/wiki/Audihttp://en.wikipedia.org/wiki/Audihttp://en.wikipedia.org/wiki/Front_mounted_intercoolerhttp://auto.howstuffworks.com/turbine.htmhttp://auto.howstuffworks.com/turbine.htmhttp://en.wikipedia.org/wiki/Engine_knockinghttp://en.wikipedia.org/wiki/Saab_Automobilehttp://en.wikipedia.org/wiki/Mitsubishi_Lancer_Evolutionhttp://en.wikipedia.org/wiki/Volkswagenhttp://en.wikipedia.org/wiki/Audihttp://en.wikipedia.org/wiki/Front_mounted_intercoolerhttp://auto.howstuffworks.com/turbine.htm


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Turbo Engines

that the turbine is attached to the compressorThe compressor is a type of centrifugal

pump -- it draws air in at the center of its blades and flings it outward as it spins and

pumps air into the cylinders. The air compressed into the cylinder raises the air5s

density 3mass unit !olume4 :any turbocharged engines ha!e a charge air cooler

3intercooler4 3that cools the compressed air to further increase its density and to

increase resistance to detonation. After passing through the intae manifold, the air

enters the engine5s cylinders, which contain a fixed !olume. &ince the air is at

ele!ated density, each cylinder can draw in an increased mass flow rate of air. igher

air mass flow rate allows a higher fuel flow rate 3with similar airfuel ratio4.

=ombusting more fuel results in more power being produced for a gi!en size or

displacement .

Inside a turbochar.er

After the fuel is burned in the cylinder it is exhausted during the cylinder5s

exhaust stroe in to the exhaust manifold The high temperature gas then continues on

to the turbine . The turbine creates bacpressure on the engine which means engine

exhaust pressure is higher than atmospheric pressure. A pressure and temperature drop

occurs 3expansion4 across the turbine , which harnesses the exhaust gas5s energy to

pro!ide the power necessary to dri!e the compressor. The compressor is a type of

centrifugal pump -- it draws air in at the center of its blades and flings it outward as it

spins.

In order to handle speeds of up to 1B,BBB rpm, the turbine shaft has to be

supported !ery carefully. :ost bearings would explode at speeds lie this, so most

S.S.G.M.C.E., Shegaon ?


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Turbo Engines

turbochargers use a 1luid bearin.. This type of bearing supports the shaft on a thin

layer of oil that is constantly pumped around the shaft. This ser!es two purposes< It

cools the shaft and some of the other turbocharger parts, and it allows the shaft to spin

without much friction.

' BASI3 TERMINOOGIES;

+ A


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Turbo Engines

realistic with the intended !ehicle use and use the A% to bias the

performance toward the desired powerband.

& 3>RA 3=enter ousing + %otating Assembly4

The =%A is essentially a turbocharger minus the compressor and turbine

housings.

(3lipped Turbine heel

Ehen an angle is machined on the turbine wheel exducer 3outlet side4, the

wheel is said to be "clipped". =lipping causes a minor increase in the wheels flow

capabilityK howe!er, it dramatically lowers the turbo efficiency. This reduction in

efficiency causes the turbo to come up on boost at a later engine speed 3ex. increased

turbo lag4. igh performance applications should ne!er use a clipped turbine wheel.

All turbos use modern unclipped turbine wheels.

' Trim

Trim is an area ratio used to describe both turbine and compressor wheels.

Trim is calculated using the inducer and exducer diameters.

xample Trim

As trim is increased, the wheel can support more airgas flow.

8 Boost Threshold;oost threshold is the engine speed at which there is sufficient exhaust gas

flow to generate positi!e manifold pressure, or boost.

: Boost Spi#e;

A boost spie is a brief period of uncontrolled boost, usually encountered in

lower gears during the onset of boost. Typically spies occur when the boost

controller cannot eep up with the rapidly changing engine conditions.

S.S.G.M.C.E., Shegaon 1B


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Turbo Engines

@ Boost 3reep;

oost creep is a condition of rising boost le!els past what the predetermined

le!el has been set at. oost creep is caused by a fully opened Eastegates not being

able to flow enough exhaust to bypass the housing !ia the Eastegates

8 0ESIGN 3ONSI0ERATIONS ;

Be1ore =e tal# about the desi.n tradeo11s/ =e need to tal# about some o1

the possible problems =ith turbochar.ers that the desi.ners must ta#e into

account

Too Much Boost;

Eith air being pumped into the cylinders under pressure by the turbocharger,

and then being further compressed by the piston, there is more danger of noc.

Cnoc#in.happens because as you compress air, the temperature of the air increases.

The temperature may increase enough to ignite the fuel before the spar plugfires.

=ars with turbochargers often need to run on higher octanefuel to a!oid noc. If the

boost pressure is really high, the compression ratio of the engine may ha!e to be

reduced to a!oid nocing.

Turbo a.;

'ne of the main problems with turbochargers is that they do not pro!ide an

immediate power boost when you step on the gas. It taes a second for the turbine to

get up to speed before boost is produced. This results in a feeling of lag when you

step on the gas, and then the car lunges ahead when the turbo gets mo!ing.

'ne way to decrease turbo lag is to reduce the inertia of the rotating parts, mainly by

reducing their weight. This allows the turbine and compressor to accelerate 6uicly,

and start pro!iding boost earlier.

Small $s ar.e Turbochar.er;

S.S.G.M.C.E., Shegaon 11
http://auto.howstuffworks.com/question90.htmhttp://auto.howstuffworks.com/ignition-system2.htmhttp://auto.howstuffworks.com/ignition-system2.htmhttp://auto.howstuffworks.com/question90.htmhttp://auto.howstuffworks.com/question90.htmhttp://auto.howstuffworks.com/ignition-system2.htmhttp://auto.howstuffworks.com/question90.htm


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Turbo Engines

'ne sure way to reduce the inertia of the turbine and compressor is to mae

the turbocharger smaller. A small turbocharger will pro!ide boost more 6uicly and at

lower engine speeds, but may not be able to pro!ide much boost at higher engine

speeds when a really large !olume of air is going into the engine. It is also in danger

of spinning too 6uicly at higher engine speeds, when lots of exhaust is passing

through the turbine.

A large turbocharger can pro!ide lots of boost at high engine speeds, but may

ha!e bad turbo lag because of how long it taes to accelerate its hea!ier turbine and

compressor.

In the next section, well tae a loo at the optional turbo features which willhelp us o!ercome these challenges.

: OPTIONA TURBO ?EATURES;

Blo=4O11 6Bypass7 !al$esB psig.

The oil outlet should be plumbed to the oil pan abo!e the oil le!el 3for wet sump

systems4. &ince the oil drain is gra!ity fed, it is important that the oil outlet points

downward, and that the drain tube does not become horizontal or go MuphillN at any

point.

S.S.G.M.C.E., Shegaon 1)


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Turbo Engines

7ollowing a hot shutdown of a turbocharger, heat soa begins. This means that

the heat in the head, exhaust manifold, and turbine housing finds it way to the turbo5s

center housing, raising its temperature. These extreme temperatures in the center

housing can result in oil coing.

To minimize the effects of heat soa-bac, water-cooled center housings were

introduced. These use coolant from the engine to act as a heat sin after engine

shutdown, pre!enting the oil from coing. The water lines utilize a thermal siphon

effect to reduce the pea heat soa-bac temperature after ey-off. The layout of the

pipes should minimize peas and troughs with the 3cool4 water inlet on the low side.

To help this along, it is ad!antageous to tilt the turbocharger about (O about the axis

of shaft rotation.:any $arrett turbos are water-cooled for enhanced durability

3eramic Turbine Blades;

=eramic turbine blades are lighter than the steel blades used in most

turbochargers. Again, this allows the turbine to spin up to speed faster, which reduces

turbo lag.

"ournal Bearin.s $s Ball Bearin.s;

The Hournal bearing has long been the brawn of the turbocharger, howe!er a

ball-bearing cartridge is now an affordable technology ad!ancement that pro!ides

significant performance impro!ements to the turbocharger.

all bearing inno!ation began as a result of wor with the $arrett :otorsports

group for se!eral racing series where it recei!ed the term the Pcartridge ball bearing5.

The cartridge is a single slee!e system that contains a set of angular contact ball

bearings on either end, whereas the traditional bearing system contains a set of

Hournal bearings and a thrust bearing

Seuential Turbochar.ers;

&ome engines use t=o turbochar.ersof different sizes. The smaller one

spins up to speed !ery 6uicly, reducing lag, while the bigger one taes o!er at higher

engine speeds to pro!ide more boost.

S.S.G.M.C.E., Shegaon 1;


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Turbo Engines

@SUPERIORIT- O? TURBO3>ARGERS ;

As pre!iously mentioned, it taes additional airflow to support the combustion

of extra fuel to increase power. To be a little more technical, it taes additional

oxygen to support the combustion of more fuel. There are ways to simulate increased

airflow without actually doing it, but such trics ha!e their short comings. 7or

example, we can get that extra oxygen by introducing oxygen-bearing compounds to

the airfuel mixture entering the engine. 0ets loo at acouple of ways this is

commonly done, and why turbocharging is a better solution. 'ne common method of

boosting power by increasing the oxygen a!ailable for combustion is to inHect nitrous

oDide, along with extra fuel, into the engine5s intae system. Ehen the nitrous oxide

enters the engine5s cylinders, compression heat causes the nitrous oxide to separate

into nitrogen gas and oxygen. That oxygen supports the combustion of the extra fuel.

A nitrous oxide inHection system can offer a substantial increase in power while the

nitrous oxide and fuel are being inHected. &uch systems are initially less expensi!e

than more durable forms of power enhancement such as turbocharging, but there are

some big disad!antages. :ost notably, the power gain only occurs while the nitrous

oxide and extra fuel are being inHected, and it taes 6uite a substantial amount of

nitrous oxide to produce significant power gains. This compressed nitrous oxide must

be carried aboard the !ehicle in a separate high-pressure tan. In most cases, it is

impractical to carry more than >B seconds worth of nitrous oxide aboard the !ehicle.

This means nitrous oxide inHection is not practical for sustained power output. !en

when used only occasionally for short spurts, the tan must be fre6uently refilled at a

nitrous oxide supply station, such as a speed shop. This is both incon!enient and an

on-going expense. Turbocharging has no on-going expenses.Another way of increasing a!ailable oxygen for combustion is to use an

oDy.en4bearin. 1uel, such as nitro methane, propylene oxide, or some other exotic

fuel blend. &uch oxygen bearing fuels can produce notable power on demand, but

they are dangerous to handle, often re6uire special fuel inHection plumbing, do not

pro!ide good fuel efficiency or economy, they tend to damage parts, and they are !ery

expensi!e. :any exotic fuels are also unstable or corrosi!e, which means they can5t

be left in the !ehicle between uses. xotic fuels are not readily a!ailable either, which

usually limits the distance a !ehicle can be dri!en to the fuel carried onboard. If you

S.S.G.M.C.E., Shegaon 1


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Turbo Engines

need the con!enience, safety, and economy of pump gasoline, such exotic fuels are

definitely not a good alternati!e or !alue. #or canexotic fuels alone generate huge

increases in power output. The only !iable solution remaining is to dramatically

increase total engine airflow to get the extra oxygen re6uired to support the

combustion of more fuel for additional power. To get this re6uired additional air flow

turbochargers are used.

) A0!ANTAGES;

Turbochar.ed en.ines are smaller and li.hter;

Eith a turbo, it taes less engine to mae more power. To mae a naturally-

aspirated engine more powerful, you need to increase its capacity and its bul.

Turbochar.ed en.ines are easier to re.ulate po=er;

ngines are constantly e!ol!ing and becoming more powerful, sometimes at

the expense of dri!er safety. 7or the racing sanctioning body concerned with safety,

controlling the speed of a turbocharged car is as simple as reducing the turbos boost.

A naturally-aspirated engine, on the other hand, must be drastically re-engineered

when the horsepower it generates becomes excessi!e.

Turbochar.ed race en.ines are less eDpensi$e/ and more reliable;

Turbocharged engines dont ha!e to rely on exotic, expensi!e materials to

reduce reciprocating mass. As naturally-aspirated engines become larger to increase

power, the stress due to the necessary increase in engine %:9 and increased

reciprocating mass placed on their !arious components also increases.

Turbochar.ed en.ines are uieter;

The turbocharger on an engine acts as a natural muffler, minimizing engine

noise and pro!iding a more spectator-friendly en!ironment at the races

Impro$ed E11iciency;

#ew, efficient turbine stages deli!er more power to engine and allow

turbochargers to spool up faster than e!er. $T ha!e eliminated old efficiency illers,

S.S.G.M.C.E., Shegaon 1>


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Turbo Engines

including on-center turbine housings, clipped turbine wheels, and anti6uated

aerodynamics with the new $T product line.

Sa1er;

A turbocharged engine can generate as much as @ times more power than anaturally aspirated 3non-turbocharged4 engine of e6ui!alent displacement. 7or

example, 7ormula 1 1.0 turbocharged engines produced more than 1BBB9. In more

standard applications, it is realistic to double the power of a gi!en engine through

turbocharging, maing !ehicles more responsi!e and safer to dri!e. Turbochargers

also pre!ent the loss of power at high altitudes, thus pro!iding significant ad!antages

to turbocharged trucs and off-road machinery.

More economical;

Turbochargers harness and recycle the energy produced by automobile

engines, transforming more of the fuel energy consumed into power by creating less

parasitic heat and friction. As a result, turbocharged engines deli!er significant fuel

cost ad!antages o!er their naturally-aspirated counterparts.

Greener;

ecause a turbocharger deli!ers more air to the engine, fuel combustion is

easier, more thorough and therefore cleaner. Today5s turbocharged diesel engines

produce BQ less #'x and ='(emissions than con!entional engines.

More ?un;

Turbochargers deli!er greater tor6ue which, in turn, translates into impro!ed

performance on the road and mae dri!ing a real pleasure.

?leDibility;

=an be efficiently used for diesel and petrol engines of hea!y, medium duty

and two wheelers as well.

S.S.G.M.C.E., Shegaon 1@


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Turbo Engines

,IMPEMENTE0 B-;

1. :itsubishi &tarion.

(. #issan &yline.

). 0otus.

;. :ercedes.

. 9orsche.

>. yundai.

@. arley *a!idson RRR.. and many more.

S.S.G.M.C.E., Shegaon 1?


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Turbo Engines

+5 3ON3USION;

Today5s auto world is the world of fast and furious automobiles. Attempts for

hie in speed and power with impro!ement in fuel economy and engine response are

thus being made. Turbo engines are one the best solutions that offers optimum speed

and power with se!eral additional features such as high boost at lower speed,

utilization of waste gas energy, high power to weight ratio, en!ironmental friendly.

Thus the turbo engines play an important role in enhancement of engine

woring parameters.

++ RE?EREN3ES;

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