A supercharger is an air compressor used for forced induction of air into an internal combustion engine whereas Turbocharger works on the exhaust gases from the cylinder for better efficiency.
In this article, I will be explaining about Supercharger VS Turbocharger and their working principle, Components along with Advantages and Disadvantages.
What is a Supercharger?
The process of forcing more charge into the engine cylinder than can be drawn by naturally aspirated piston action to get more power is called Supercharger.
Parts of Supercharger:
The four main components of a centrifugal supercharger are
- The Volute (compressor housing)
- Impeller and
Working Principle of Supercharger:
It is fitted before the Intake valve of the cylinder so that air can be compressed in the supercharger and allowed it to be forced into the cylinder via the Intake valve. It is used to increase engine power, efficiency, torque by compressing the air in multi-stages for increasing the quantity of air, pressure, and temperature.
The greater mass flow-rate provides more oxygen to support combustion in the cylinder compared to the naturally aspirated engine.
Supercharger allows more fuel to be burned and thereby more work is said to be done per cycle which increases the power output of the engine.
The Power to the supercharger comes mechanically from the engine’s crankshaft via a belt, gear, shaft, or chain.
Super Charger increases the pressure of the A/F mixture and supplies at a higher pressure than atmospheric pressure.
The supercharged engine produces higher power up to 40% to that of the normal engine.
It also increases torque by 40%.
At higher altitudes, it helps by increasing the density of the air fed to the engine.
Types of Superchargers:
According to the method of compression, there are two main types of superchargers.
- Positive displacement (Example: Twin-screw, roots)
- Dynamic compressors (Example: Centrifugal)
A Positive Displacement Pump has a decreasing cavity on the discharge side and an expanding cavity on its suction side.
Centrifugal Type Supercharger:
A/F mixture enters the impeller at the center and passes through the impeller and diffuser vanes. Finally, it enters volute casing and the mixture goes to the engine from the casing.
- The pressure is increased by 30%
- Impeller speed → 80000 revs/min
- Impellers are made of duralumin/alloy steels to withstand high steels.
In Root’s Supercharger, there are two rotors of epicycloids shape, each rotor keyed to its shaft.
- One rotor is connected to others by means of gears.
- Gears are of equal size and two rotors rotate at the same speed.
- Operates like a gear pump.
- The mixture at the outlet of the supercharger is at high pressure.
Advantages of Supercharger:
Here are some advantages of Supercharger:
- Higher power output.
- Quicker acceleration of the vehicle.
- Reduced smoke from exhaust gases.
- Cheaper than a turbocharger.
Disadvantages of Supercharger:
There are some disadvantages of Supercharger and those are:
- Draws power from the engine.
- Increased heat generation.
What is Turbo Charger?
It is a device driven by a turbine and it is used to increase the performance and efficiency of an Internal Combustion Engine, by putting more compressed air to the engine cylinder.
Components of Turbocharger:
The components of Turbocharger is as follows:
- Engine cylinder (Inlet and Exhaust Valve)
Working Principle of Turbocharger:
It is a centrifugal compressor which is powered by a turbine that is driven by means of engine’s exhaust gases.
Engine’s volumetric efficiency can be improved by increasing the intake density.
The turbine converts the engine exhaust pressure energy and kinetic energy into rotational power, which is in turn used to drive the compressor.
Supercharger VS Turbocharger:
The difference between Supercharger and Turbocharger is shown in the Tabular column below.
|They are basically compressors.||Turbos consist of both- turbine & air compressor mounted on the same shaft.|
|They draw power from the engine via a belt.||Turbocharger extracts the power from exhaust gases.|
|Cost of Supercharger is less than the Turbocharger||Cost of Turbocharger is more than the Supercharger|
|The supercharger is connected to the intake manifold of the vehicle.||Since it is a combination of both turbine & compressor, the turbine is connected to exhaust pipe while compressor to intake.|
|Less Efficient||More Efficient|
|Maintenance is Easy.||Difficult to maintain|
|Suitable for engines with smaller displacements.||Suitable for engines with higher displacements.|
|As soon as the engine starts, Superchargers start working.||Turbos won’t start operating until a sufficient amount of exhaust gases are produced.|
This is a detailed explanation of the Supercharger and Turbocharger, and also I mentioned the difference between Supercharger and Turbo Charger. If you have any doubts, feel free to ask in the comments section.
References [External Links]:
- A review on turbocharger and supercharger – RS Publication
- Overview of Electric Turbocharger and Supercharger for Downsized Internal Combustion Engines
- Comparison of a Supercharger vs. a Turbocharger in a Small Displacement Gasoline Engine Application
- Image 1: By CZmarlin — Christopher Ziemnowicz. Thank you! – Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=5114914
- Image 3: By ATI ProCharger – www.procharger.com, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=18264092
- Image 4: By Inductiveload – Own workBased on File:Rotary_piston_pump.svg, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=11297699
- Image 5: By No machine-readable author provided. Sfoskett~commonswiki assumed (based on copyright claims). – No machine-readable source provided. Own work assumed (based on copyright claims)., CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=423186
- Image 6: By Quentin Schwinn (NASA) – This image or video was cataloged by Glenn Research Center of the United States National Aeronautics and Space Administration (NASA) under Photo ID: C-2003-1451., Public Domain, https://commons.wikimedia.org/w/index.php?curid=123057
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- Video: By Engineering Explained