How Does a Turbo Charger Work?

Purpose

A turbo charger is used in high performance vehicles and can be added as an after-market option to most cars as a cheap and energy efficient method of increasing an engine's power output. It should be noted that turbo chargers are different from super chargers, as turbo chargers do not take their motive energy from the engine's mechanical drive.

Form

A turbo charger is comprised of two separate disc-shaped housings that sit bolted side by side. Each housing contains a ceramic fan fitted around a central spindle that connect to one another, thus if one fan blade spins, so does the other. One of the housings is called the turbine section, while the other is called the compressor section. The turbo charger is bolted to the housing of the engine's exhaust manifold. Instead of the exhaust leading directly from the engine's cylinders to the exhaust pipe, the turbine section sits between them. Likewise, the compressor section sits between the air filter of the carburetor and the fuel/air mix intake valve of the engine's cylinders.

Function

When the car's engine starts, air passes through the carburetor, mixes with fuel from the fuel injectors, passes through the compressor section, and into the cylinders to fire. Once the cylinders start to fire, the exhaust they produce is forced out through the turbine section of the turbo charger. This causes the fan within the turbine section to turn, which makes the fan in the compressor section turn. As the fan in the compressor section turns faster, it forces more air/fuel into the cylinders for each successive round of firings, which generates more exhaust and only makes the turbine turn faster. In this way, by forcing as much air/fuel into the cylinders as they can hold, each round of firings generates a greater combustion and hence more power is produced by the engine. The only threshold for this process is when the rate of firings increases to such a point that the compressor doesn't have enough time to force any more air into the cylinders.

References

• Turbo Chargers Explained
• How Turbo Chargers Work