2. Supercharged system
Another innovation in internal combustion engines of the piston type that boosts performance is the
supercharger. It is an air compressor that raises the pressure or density of air that enters the combustion
chamber of an engine to facilitate heavy duty operation . As you may know, a vehicle engine gets its
mechanical motion from the combustion chamber using a fuel/air mixture. In order to enhance the amount
amount of fuel combined and burned as well as the pressure of the air entering the combustion chamber, a
a supercharger is added. This results in the high engine performance.
3. General Operation of a supercharger.
A supercharger is normally driven mechanically by the engine via a belt
connected to the crankshaft.
As the supercharger is driven, it sucks in air from the outer atmosphere
and compresses it, increasing the air temperature in the process.
The hot, compressed air is sent to the intercooler to cool down. The
cooled air will now become denser, allowing more fuel to be injected
and thus more power.
The cooled air is finally sent to the engine to mix with fuel and
combust.
6. Roots superchargers
The roots supercharger traps air in a chamber between the rotor and the housing, in
the void between the rotor's lobes, and transports this trapped air to the outlet side,
at the engine's intake manifold. By virtue of moving air into the manifold at a rate
higher than the engine consumes it, pressure is built.
Air trapped in the pockets between the lobes of the meshing rotors is carried between
the fill and discharge sides as the rotors spin. Massive amounts of air enter the intake
manifold and "stack up" to create positive pressure. As a result, Roots superchargers
are essentially air blowers.
Roots superchargers are typically large and mounted on the engine's hood. They are
popular in muscle cars and hot rods because they protrude from the hood. They are,
however, the least efficient supercharger due to two factors: they add weight to the
vehicle and move air in discrete bursts rather than in a smooth and continuous flow.
7. Twin-screw Superchargers
This device begins its operation by driving a pulley and
transmitting power to an input shaft, which causes the rotors to
move in the opposite direction. One of its rotors has taper teeth,
while the other has warm gear teeth. When both sides of the rotor
pocket mesh, air is squeezed between them. When air begins to
compress by both sides of the rotor's pockets, it flows horizontally
in auxiliary motion all the way to the discharge side in radial
motion to into the engine.
8. Centrifugal superchargers
A centrifugal supercharger powers 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. As the air is drawn in at the hub of the impeller,
centrifugal force causes the air to radiate outward. That means the air leaves the
impeller at high speed but low pressure. A diffuser – a set of stationary vanes that
surround the impeller – converts the high-speed, low-pressure air to low-speed,
high-pressure air. Air molecules slow down when they hit the vanes, which reduces
the velocity of the airflow and increases pressure.
9. Function
A supercharger is a mechanically powered component that uses
an air compressor or blower to pressurise the air being pumped
into the intake manifold. The level of air entering the cylinder
during the intake stroke is raised due to the high pressure. As
each engine intake circle receives more oxygen, superchargers
enable the engine to burn more fuel and perform more work.
Through the use of a gear, belt, shaft, or chain attached to the
engine's crankshaft, these power components are mechanically
propelled.
10. Advantages Of Using A supercharger
Increased horsepower: adding a supercharger to any engine is a quick
solution for a power boost.
No lag: because the supercharger is driven by the engine’s crankshaft, it
does not suffer from lag like a turbocharger does.
Low RPM boost: Superchargers provide good power at low RPM compared
to turbochargers.
Price: superchargers are a cost effective way of increasing horsepower.
11. Disadvantages Of Using A
Supercharger
Less efficient: superchargers use engine power to produce more engine
power. Therefore they are not as efficient as turbochargers.
Reliability: any form of forced induction system will naturally impose a
negative impact on the longevity of the engine because the engine
internals will be exposed to higher pressures and temperatures.
