What Is a Supercharger?
A supercharger is a device that increases the power output of an engine by forcing compressed air into the engine’s cylinders. This process enhances the engine’s ability to burn fuel, thereby boosting its power. Superchargers are particularly beneficial for smaller engines, enabling them to produce more power than their size would typically allow.
Principle of Superchargers
Superchargers function by using the engine’s crankshaft and a belt. The belt’s rotation activates a compressor, which then compresses the air and feeds it into the cylinders. This is different from a turbocharger, which uses the engine’s exhaust gases to power the compressor.
Uses of Superchargers
Superchargers are effective even at low engine speeds, as they are directly powered by the engine. However, their efficiency can decrease at higher speeds due to increased load and reduced air compression efficiency. Superchargers are typically used in lighter vehicles and are suited for city driving, where high RPM ranges are less frequently used.
In recent years, the use of superchargers has declined due to the development of more efficient turbochargers, which offer better compression efficiency at high RPMs and less engine loss.
Types of Superchargers
There are several types of superchargers, classified based on the type of compressor they use:
- Roots Type: Uses rotors for air intake and discharge, known for its simplicity and low cost.
- Centrifugal Type: Employs a direct rotation of the compressor using the crank’s power, similar to turbochargers, but less responsive.
- Lysholm Type: Utilizes helical rotors, offering less vibration and high performance, but at a higher cost.
- Scroll Type: Involves a stationary and a moving spiral wing to compress air.
- Sliding Vane Type: Features a cylindrical rotor in an elliptical housing for air compression.
- Reciprocating Type: Compresses air using a piston’s up-and-down movement.
Each type has unique characteristics, with the air supply being somewhat proportional to the engine’s RPM.
Other Information on Superchargers
Electric Superchargers
Electric superchargers were developed to overcome the limitations of traditional superchargers at high RPMs. They maintain air compression efficiency at high speeds and are typically used in light vehicles with smaller engines. However, due to their lower airflow compared to superchargers and turbochargers, electric superchargers are often used as supplemental devices, enhancing the low RPM range of turbochargers.