- ADVANTAGES AND DISADVANTAGES OF USING A FORWARD-FAN AND AN AFT-FAN TYPE OF ENGINE
- Highly fuel-efficient
- As a result of producing more thrust for the same quantity of fuel, the engine is extremely fuel-efficient.
- Increased thrust
- More air is being drawn into the engine.
- Protection and control
- The fan is covered by the cowling, and the aerodynamics of the fan may be easily controlled because the cowling is enclosed.
- Larger frontal area
- The frontal area of a forward-fan engine is significantly bigger than that of a reverse-fan engine since the engine diameter is enlarged as a result of the fan itself.
- Has greater complexity
- The engine has greater complexity due to the addition of ducts and multiple shafts.
- Not efficient in supersonic speed
- Forward-fan engines are most efficient only at subsonic speeds. That is why most commercial aircraft are equipped with forward-fan engines.
- Simple design and low-cost
- Aft-fan type engine, in 1956, relative to a turbojet engine, is known to be uncomplicated and low-cost development since it was derived from the aforementioned relative engine.
- Hot gas leakage
- The reason behind this is the low-pressure turbine comes first before the fan. Hence, leakage occurs from the turbine to the fan.
- It cannot contribute to air compression at the inlet
OPERATIONS OF TURBOFAN ENGINES
A turbofan engine is a type of gas turbine jet engine that produces high levels of thrust. As a result, its main operation is divided into two halves, which are the cold part and the hot portion. The cold section begins with the intake of air from the free stream into the engine, which is the first step in the process. Second, the air will be compressed to high pressure before being released.
After that, the fuel and air mixture will be combusted, resulting in an increase in both pressure and heat. As a result, the hot segment has officially begun. Following that, high-pressure exhaust gases will be expanded, via the turbine portion, in order to provide energy for the generator. Finally, the burned fuel and air combination, which has now become a high-speed parameter, will escape the engine through the exhaust nozzle, generating the push required by the airplane for takeoff and landing. Turbofan engines are designed to generate additional thrust by redirecting secondary airflow around the combustion chamber during operation. Because the incoming air has two pathways,
one around the engine and the other via the core, a turbofan engine has two sources of thrust, one from the fan and one from the core, which results in a more efficient engine.
To summarize, a turbofan engine runs through a number of processes, the most important of which are intake, compression, ignition, and exhaust. It is possible for the air entering the engine to enter by one of two routes: around the engine or through the core. These two pathways are essentially the sources of forwarding momentum.
Sultan l. (1963, March 1). What provides the greatest thrust in a high-bypass turbofan engine? Aviation Stack Exchange. Retrieved April 29, 2022, from https://aviation.stackexchange.com/questions/15510/what-provides-the-greatest-thrust-in-a-high-bypass-turbofan-engine
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