Supercharging was a common technique used in aircraft piston engines to make up for the decreased air density at high altitudes, In the twenty-first century, automakers have switched to using turbochargers instead of supercharging to lower fuel consumption and boost power outputs.
According to the current classification, a supercharger is different from a turbocharger in that the former is driven by the kinetic energy of exhaust gases, while the latter is propelled physically (typically by a belt from the engine crankshaft).
Nevertheless, a turbocharger was referred to as a “turbosupercharger” and was regarded as a kind of supercharger until the middle of the 20th century. The first supercharged engine was constructed in 1878, and it was initially used in automobile engines in the 1920s and aviation engines in the 1910s.
To increase power for a given displacement in an internal combustion engine, a supercharger compresses the intake gas and forces more air into the engine. Well, in this reading, I’ll be exploring what Supercharger is, its application, diagram, types, advantages and disadvantages & how it’s work.
Let’s Get Started!
What Is Supercharger?
An air compressor known as a supercharger raises the air pressure that is delivered to an internal combustion engine. Because the engine burns more fuel and receives more oxygen during each intake cycle, this contributes to a greater power output.
Superchargers may be mechanically driven by a crankshaft-connected belt, shaft, or chain in an engine. There are two kinds of superchargers on the market: dynamic compressors and positive displacement compressors.
Simply said, at all engine speeds (RPM), the positive displacement superchargers provide a steady rise in pressure. Dynamic Compressor superchargers, on the other hand, produce exponential speed pressure over their threshold but less pressure at lower speeds.
By supplying a greater amount of oxygen, superchargers enable the engine to burn more fuel and perform additional work within each intake cycle. These power-enhancing devices are driven mechanically, using gears, belts, shafts, or chains connected to the engine’s crankshaft.
Superchargers are mechanical devices that increase the amount of air pushed into the intake manifold of an internal combustion engine, thereby increasing fuel combustion and power output.
They are commonly used in high-performance vehicles, aircraft engines, marine engines, diesel engines, off-road vehicles, emergency services vehicles, custom builds and kit cars, hybrid and electric cars, and industrial applications.
High-performance vehicles often use superchargers to increase engine power and torque, resulting in better acceleration and maximum speed. They are also used in various motorsport disciplines, such as off-road, drag, and road racing, to provide racing cars with an advantage over other vehicles on the track. Superchargers are also used in aircraft engines to maintain engine performance at various altitudes when air density fluctuates.
Marine engines often employ marine superchargers for faster acceleration and faster speeds. Diesel engines can also benefit from superchargers, as they can increase the low-end torque of off-road vehicles, such as trucks and SUVs, which are necessary for climbing steep terrain and carrying large loads.
Industrial applications also benefit from superchargers, as they improve the efficiency and performance of engines used in power generation or industrial operations.
To gain a solid understanding of superchargers, it is recommended to take the SSC JE ME Previous Years Papers and the SSC JE Mechanical practice exams, as well as enroll in the AE/JE Mechanical coaching program.
How Does Supercharger Works?
An internal combustion engine ignites a mixture of fuel and air by drawing air into a cylinder and compressing it there. After being lit, it produces a piston power stroke before transferring energy to the wheels. A vehicle’s displacement determines the matching degree of performance that the engine can provide.
A bigger engine may provide the necessary power when required, but so can a forced induction device like a supercharger. Superchargers run on belts and are typically driven by the crankshaft of an engine. Unlike turbochargers, which use the waste heat from the exhaust, this kind of forced induction doesn’t use that heat.
The engine of a supercharged vehicle draws air via the intake, hood scoops, and any other openings while it is operating. The air is then compressed by the supercharger, increasing its density and pressure. This way the engine receives more air through the same intake, which allows it to burn more fuel resulting in a boost in performance.
But there’s an initial expense associated with that surge. notably, a 20% reduction in horsepower. On the other hand, a supercharger produces far more horsepower than the belt drive takes from the engine, thus the net increase in horsepower is somewhere between 30% and 50%.
The Roots supercharger, also known as a root-blower, is a type of supercharger that traps and compresses air through two meshing lobes. This mechanism increases oxygen availability, allowing the engine to take in more fuel and run faster. However, it produces a lot of heat energy and is typically mounted near the top of an engine.
The Centrifugal supercharger uses a belt-driven impeller attached to the crankshaft to pull in air, compressing it to high pressure and low velocity. The compressed air is released through the exit valve, increasing the air temperature.
However, this high thermal efficiency produces less heat, and the density of the hot air may prevent expansion in the combustion chamber. To ensure the supercharger operates well, it is essential to cool the heated air, which is lowered in large part by the intercooler.
The Twin-Screw supercharger draws air through two meshing lobes resembling worm gears, drawing air through two meshing lobes that resemble worm gears. The rotor lobes generate pockets that trap air, similar to the Roots supercharger.
However, the air within the rotor housing is compressed by the twin-screw supercharger due to the conical taper of the rotors, causing the air pockets to contract as air passes from the fill side to the discharge side.
Superchargers offer numerous advantages, including increased power production, improved fuel atomization, better scavenging, torque characteristics, quick vehicle acceleration, and seamless burning.
They also reduce smoke emissions, use certain fuels, enhance mechanical effectiveness, and reduce diesel knock propensity. However, they also have disadvantages such as increased detonation tendency in SI engines, increased gas loading, increased cooling requirements, increased thermal stress, and increased heat loss due to increased turbulence.