Since the invention of the internal combustion engine, automotive engineers, speed junkies and race car designers have been searching for ways to boost its power. One way to add more power is build a bigger engine. But the bigger engine is lack of problems like gain more weigh on the car, cost more to build and maintenances. Another way to add more power is to make a normal-sized engine more efficient. You can accomplish this by forcing more air into the combustion chamber. More air means more fuel can be added, and more fuel means a bigger explosion and greater horsepower. Adding a supercharger is great way to achieve forced air induction.

Figure 1. Ford Mustang 2015-2017 Supercharger [1]

The supercharger as shown in Figure 1 is extra added part of engine in air compressor that increases the pressure or density of air supplied to an internal combustion engine that gives each intake cycle of the engine more oxygen, letting it burn more fuel and do more work, thus increasing power of engine. Power of supercharger can be provided mechanically by means of a belt, gear, shaft, or chain connected with engine’s crankshaft.

Basically, supercharger is part of compressor. The first compressor is Roots-style compressor invented by G. Jones from Birmingham, England. In 1878, Dugard Clerk made the world’s first functional engine with supercharger using two-stroke engine and then was patented by many engineer until Gottlieb Daimler included supercharger in engine in 1885. Mercedes or Daimler Benz soon introduce to the world the first automobile that used supercharger with Roots-style compressor in their model like 6/25/40 hp and 10/40/65 hp, which is called kompressor. On March 24, 1878 Heinrich Krigar from Germany resembled the design of Roots-style compressor into the first ever Screw-type compressor but because technology of the time was not sufficient to produce such a unit, the Screw-type compressor progress was totally stop

There are many types of superchargers from Roots, Twin-Screw and Centifugal (Turbocharger). The difference is how they move the air into intake manifold of the engine. Roots and Twin-Screw superchargers use different types of meshing lobes, and a centrifugal supercharger uses an impeller, which draws air in. Although all of these designs provide a boost, they differ considerably in their efficiency. Each type of supercharger is available in different sizes, depending on whether you just want to give your car a boost or compete in a race.

The supercharger is famous of performance improvement that quickly increase horsepower of engine but how exactly the supercharger work together with car engine? Answer is quite simple but sometimes complicated too, as shown in Figure 2. Once air is drawn into the engine, it will be combined with fuel to form the charge that creates energy. The energy turned into kinetic energy through a chemical reaction known as combustion, as shown in Figure 2. The spark plug initiates this chemical reaction by igniting the charge. As the fuel undergoes oxidation, a great deal of energy is completely released. The force of this explosion, concentrated above the cylinder head, drives the piston down and creates a reciprocating motion that is eventually transferred to the wheels.

Figure 2. Work method of supercharger step by step

We all know anything in this universe sure have something good behind that or maybe bad about those things. Like positive and negative, the supercharger have some high expectation performance for any automobile that used this thing. But because of high expectation, the uncomfortable zone was suddenly come up accidentally.

     ADVANTAGES :

1.      Horsepower increased a lot which mean making the engine into powerful

2.      Anti lag – time between the driver depressing the gas pedal and the engine’s response

3.      Easy to install – superchargers can be bolted to the top or side of the engine

4.      Can be shut down normally without any procedure

DISADVANTAGS :

1.      Characteristic – with the crankshaft drives, some horsepower from engine are stealed

2.      Added strain on the engine which make driver need to strong handle the extra boost

3.      Maintain and service are expensive and long period

Despite their disadvantages, superchargers are still the most cost-effective way to increase horsepower. Superchargers can result in power increases of 50 to 100 percent, making them great for racing, towing heavy loads or just adding excitement to the typical driving experience.

contribution by : Richard Martin (ARE sem 2 2017/2018)