Turbocharger

A turbocharger, or turbo (colloquialism), from the Greek "τύρβη" (mixing/spinning) is a forced induction device used to allow more power to be produced for an engine of a given size.[1][2] A turbocharged engine can be more powerful and efficient than a naturally aspirated engine because the turbine forces more intake air, proportionately more fuel, into the combustion chamber than if atmospheric pressure alone is used.
Turbochargers were originally known as a turbosuperchargers when all forced induction devices were classified as superchargers, nowadays the term "supercharger" is usually applied to only mechanically-driven forced induction devices.[3] The key difference between a turbocharger and a conventional supercharger is that the latter is mechanically driven from the engine often from a belt connected to the crankshaft, whereas a turbocharger is driven by the engine's exhaust gas turbine. Compared to a mechanically-driven supercharger, turbochargers tend to be more efficient but less responsive. Twincharger refers to an engine which has both a supercharger and a turbocharger.
Turbos are commonly used on truck, car, train and construction equipment engines. Turbos are popularly used with Otto cycle and Diesel cycle internal combustion engines. They have also been found useful in automotive fuel cells

Operating principle

In most piston engines, intake gases are "pulled" into the engine by the downward stroke of the piston[16][17] (which creates a low-pressure area), similar to drawing liquid using a syringe. The amount of air which is actually inhaled, compared with the theoretical amount if the engine could maintain atmospheric pressure, is called volumetric efficiency.[18] The objective of a turbocharger is to improve an engine's volumetric efficiency by increasing density of the intake gas (usually air).
The turbocharger's compressor