1. 1. SEMINAR ONSUPERCHARGER
2. 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.
3. Supercharger,The Engine Booster A supercharger is an equipment that compresses the air
being delivered to an engine, allowing the combustion chamber to be overfilled without
enlarging the space. The higher concentration of oxygen provided by a super- charger is
matched with a larger amount of fuel from the fuel injectors thus boosting the power of the
engine. A typical supercharger
4. Why Supercharger??
• Increases the power of an engine.
• A supercharger spinning at 50,000 RPM translates to a boost of about six to nine pounds
per square inch(psi)
• Increases the torque produced.
• An efficiently working supercharger can achieve the same speed in one third time.
• Necessary in aero-planes as they have less oxygen at high altitudes.
• Ensures complete combustion of the fuel. • Reduces pollution to some extent.
5. 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 an engine to operate
perfectly.
• Thus superchargers provides more air by compressing air above atmospheric pressure ,
hence providing more fuel into the charge & would make for a more powerful explosion . •
Thus: Increased Power, Torque and Speed is achieved.
6. A standard engine with the addition of a supercharger
7. Classification of Superchargers Based on method of compression, Superchargers can be
classified as:-
1. Positive-displacement type, which deliver a nearly-fixed volume of air per revolution at all
speeds and a fairly constant level of boost regardless of engine speed.
2. Dynamic compressors rely on accelerating the air to high speed and then exchanging that
velocity for pressure by diffusing or slowing it down & deliver increasing boost with increasing
engine speed.
8. Commonly used Superchargers
2. 9. 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.
10. Roots supercharger As the meshing lobes spin, air trapped in the pockets between the lobes
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. Working:- Working of a roots supercharger
11. 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. Working of a twin-screw
supercharger
12. 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. Twin-
screw supercharger
13. Centrifugal Supercharger • A centrifugal supercharger works by powering an impeller (a
device similar to a rotor) at very high speeds to quickly draw air into a small compressor
housing. • Impeller speeds can reach ‘50,000 to 60,000 RPM’. • Centrifugal superchargers are
the most efficient and the most common induction systems. • They are small, lightweight and
attachable to the front of the Engine.
14. 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. Working of a centrifugal supercharger
15. Drives 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.
16. Supercharger, An edge over turbocharger • Superchargers do not suffer lag:-
Superchargers have no lag time because they are driven directly by the crankshaft, whereas
Turbochargers suffer from lag because it takes a few moments before the exhaust gases
reach a velocity that is sufficient to drive the impeller/turbine. • Modification of the exhaust
system:- Installing a turbocharger requires extensive modification of the exhaust system, but
superchargers can be bolted to the top or side of the engine , that makes them cheaper to
install and easier to service and maintain.
17. Contd…. Shutdown procedure:- No special shutdown procedure is required with
superchargers as they are not lubricated by engine oil . They can be shut down normally.
Turbochargers must idle for about 30 seconds or so prior to shutdown so the lubricating oil
has a chance to cool down.
18. Nothing is perfect • It derives power from the engine itself: Crankshaft drives superchargers
so they steal some of the engine's horsepower. A supercharger can consume as much as 20
percent of an engine's total power output. (But because a supercharger can generate as much
as 46 percent additional horsepower, I think the trade-off is worth it). • An added strain on the
engine: Supercharging puts an added strain on the engine, which needs to be strong to
3. handle the extra boost and bigger explosions. • An extra expense : Heavy-duty components ,
design complexity & maintenance add an extra burden on the expenses.
19. Conclusion • Despite their disadvantages, superchargers are still the most cost-effective way
to increase horsepower. • Superchargers can result in power increase of 50 to 100 percent,
making them great for racing, towing heavy loads or just adding excitement to the typical
driving 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.
20. THANK YOU!
