Air intake

An intake or (for aircraft) inlet is an opening on a car or aircraft body capturing air for operation of an internal combustion engine.

Because the modern ground vehicle internal combustion engine is in essence a powerful air pump, like the exhaust system on an engine, the intake must be carefully engineered and tuned to provide the greatest efficiency and power. An ideal intake system should increase the velocity of the air until it travels into the combustion chamber, while minimizing turbulence and restriction of flow.

However, in aircraft, particularly supersonic aircraft, the purpose of the intake is to slow and increase the pressure of the air.

Early automobile intake systems were simple air inlets connected directly to carburetors. The first air filter was implemented on the 1915 Packard Twin Six.

The modern automobile air intake system has three main parts, an air filter, mass flow sensor, and throttle body. Some modern intake systems can be highly complex, and often include specially-designed intake manifolds to optimally distribute air and air/fuel mixture to each cylinder. Many cars today now include a silencer to minimize the noise entering the cabin. Silencers impede air flow and create turbulence which reduce total power, so performance enthusiasts often remove them.

All the above is usually accomplished by flow testing on a flow bench in the port design stage. Cars with turbochargers or superchargers which provide pressurized air to the engine usually have highly refined intake systems to improve performance dramatically.

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Wikipedia