Final answer:
Bypassed air in a turbofan engine is more efficient at creating engine thrust because it contributes to a higher propulsive efficiency. It is accelerated by the fan at the front of the engine and does not go through the combustion process, reducing the amount of fuel required. This bypass thrust leads to a more efficient propulsion system.
Step-by-step explanation:
In a turbofan engine, bypassed air is more efficient at creating engine thrust because it contributes to a higher propulsive efficiency. Propulsive efficiency is a measure of how effectively an engine converts fuel into useful propulsion. By bypassing some of the air around the combustion chamber, the turbofan engine can achieve a higher bypass ratio, which leads to a more efficient propulsion system.
The bypassed air in a turbofan engine is accelerated by the fan at the front of the engine and creates additional thrust. This is known as bypass thrust. The bypassed air does not go through the combustion process, so it does not need to be heated, reducing the amount of fuel required.
For example, a high-bypass turbofan engine used in commercial aircraft can have a bypass ratio of around 5:1 or higher, meaning that for every unit of air passing through the combustion chamber, five units of air are bypassed. This bypassed air contributes significantly to the overall thrust of the engine, making it more efficient.