super and turbo charger

7/28/2019 Super and Turbo Charger

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SUPERCHARGERS


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Content..Supercharger , the engine booster.

Why supercharger ??

How it works ???

Working diagram of supercharger.

Classification of supercharger.

History.

Roots supercharger.

Twin-Screw Supercharger.

Centrifugal Supercharger.

Drives used in Supercharger.Supercharger, An edge over turbocharger

Nothing is perfect.

Conclusion.


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HISTORY

The Roots supercharger is the oldest design of supercharger.

Philander and Francis Roots patented the design in 1860 as a

machine that would help ventilate mine shafts.

In 1900, Gottleib Daimler for the first time included a Roots

supercharger in a car engine.


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SUPERCHARGER,

THE ENGINE BOOSTERA supercharger is an equipment that compresses the airbeing delivered to an engine, allowing the combustionchamber to be overfilled without enlarging

the space.

The higher concentration of

oxygen provided by a super-

charger is matched with a largeramount of fuel from the fuel injectors

thus boosting the power of the

engine.A typical supercharger


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WHY SUPERCHARGER??

Increases the power of an engine.

A supercharger spinning at 50,000 RPM translatesto a boost of about six to nine pounds per squareinch(psi).

Increases the torque produced.

An efficiently working supercharger can achievethe same speed in one third time.

Necessary in aero-planes as they have lessoxygen at high altitudes.

Ensures complete combustion of the fuel.

Reduces pollution to some extent.


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PRINCIPLE OF WORKING

More fuel + More air = Bigger explosion = Greater

horsepower.

NOTE:

But we cannot simply pump more fuel into the engine.

The chemically correct mixture (14 : 1 :: air : fuel) is essential for anengine to operate perfectly.

Thus superchargers provides more air by compressing air above atmospheric

pressure , hence providing more fuel into the charge & would make for amore powerful explosion .

Thus: Increased Power , Torque and Speed is achieved.


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A standard engine with the addition of a supercharger


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CLASSIFICATION OF SUPERCHARGERS

Based on method of compression, Superchargers can be classifiedas:-

1. Positive-displacementtype, which deliver a nearly-fixed volume of air per revolution at all speeds and afairly constant level of boostregardless of enginespeed.

2. Dynamic compressors rely on accelerating the air tohigh speed and then exchanging that velocity forpressure by diffusing or slowing it down & deliverincreasing boostwith increasing engine speed.


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COMMONLY USED SUPERCHARGERS

Superchargers

RootsSuperchargers

Twin-ScrewSuperchargers

CentrifugalSuperchargers


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As the meshing lobes spin, air trapped in the pockets between thelobes is carried between the fill side and the discharge side & Large

quantities of air move into the intake manifold and "stack up" to

create positive pressure.

Roots superchargers are usually large and sit on top of the engine.

Roots superchargers are the least efficient supercharger for two

reasons:-

1.)They add more weight to the vehicle.

2.)They provide air in discrete bursts instead of

providing in a smooth and continuous manner.

ROOTS SUPERCHARGER

Working:-


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Roots supercharger


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TWIN-SCREW SUPERCHARGER

A twin-screw supercharger operates by pulling air through a pair

of meshing lobes that resemble a set of worm gears.

A twin-screw supercharger compresses the air inside the rotor

housing (That's because the rotors have a conical taper, which

means the air pockets decrease in size as air moves from the fill

side to the discharge side).

As the air pockets shrink,

the air is squeezed into a smaller space.

Twin-screw supercharger


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Contd

Thus twin-screw superchargers are more

efficient compared to roots supercharger.

They cost more because the screw-type rotors

require more precision in the manufacturing

process.

They also make a lot of noise.

The compressed air exiting the discharge

outlet creates a whine or whistle that must be

checked with noise suppression techniques.


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CENTRIFUGAL SUPERCHARGER

A centrifugal supercharger works by powering an impeller

(a device similar to a rotor) at very high speeds to quickly drawair into a small compressor housing.

Impeller speeds can reach 50,000 to 60,000 RPM.

Centrifugal superchargers arethe most efficient and the most

common induction systems.

They are small, lightweight and

attachable to the front of the

Engine.


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WORKING:-

As the air is drawn in the hub of the impeller, centrifugal force causes it

to radiate outward.

The air leaves the impeller at high speed, but low pressure.

A diffuser converts the high-speed , low-pressure air to low-speed ,

high-pressure air.

Thus pressurized air is achieved.

centrifugal supercharger


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DRIVERS USED IN SUPERCHARGER

Mechanical:-

Belt (V belt, Toothed belt & Flat belt).Gear drive.

Chain drive.

Exhaust gas turbines:-

Axial turbine.

Radial turbine.

Other:-

Electric motor.


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SUPERCHARGER, AN EDGE OVER

TURBOCHARGERS Superchargers do not suffer lag:- Superchargers have no

lag time because they are driven directly by thecrankshaft, whereas Turbochargers suffer from lag

because it takes a few moments before the exhaustgases reach a velocity that is sufficient to drive theimpeller/turbine.

Modification of the exhaust system:- Installing aturbochargerrequires extensive modification of theexhaust system, but superchargers can be bolted to thetop or side of the engine , that makes them cheaper to

install and easier to service and maintain.


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Contd.

Shutdown procedure:-No special shutdown procedure is required withsuperchargers as they are not lubricated by

engine oil . They can be shut down normally.Turbochargers must idle for about 30 seconds orso prior to shutdown so the lubricating oil has achance to cool down.


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NOTHING IS PERFECT

It derives power from the engine itself: Crankshaft drivessuperchargers so they steal some of the engine's horsepower. Asupercharger can consume as much as 20 percent of an engine'stotal power output.

(But because a supercharger can generate as much as 46 percentadditional horsepower, I think the trade-off is worth it).

An added strain on the engine: Supercharging puts an addedstrain on the engine, which needs to be strong to handle the extraboost and bigger explosions.

An extra expense : Heavy-duty components , design complexity &maintenance add an extra burden on the expenses.


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CONCLUSION

Despite their disadvantages, superchargers are still themost cost-effective way to increase horsepower.

Superchargers can result in power increase of 50 to

100 percent, making them great for racing, towingheavy loads or just adding excitement to the typicaldriving experience.

It is a must use component in an airplanes.

With the use of high octane premium-grade gas , I

think it is a miracle invention for speed junkies.


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QUERRIES??


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THANK YOU!

super and turbo charger

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