Turbine engines Flashcards
What is the primary function of an aircraft engine, aside from providing thrust?
The primary function of an aircraft engine, aside from providing thrust, is to supply hydraulic power, electric power, and bleed air for the pneumatic system.
What are the two main types of aircraft engines?
The two main types of aircraft engines are piston type engines and gas turbine engines.
Why are gas turbine engines preferred over piston engines for larger aircraft?
Gas turbine engines are preferred over piston engines for larger aircraft because they can operate at high altitudes, provide high thrust and torque, and are more suitable for high-speed flight.
What are the key components of a gas turbine engine?
The key components of a gas turbine engine are the air inlet, Low and High-pressure compressor section (LPC and HPC), combustion section (diffuser and combustor), turbine section (LPT and HPT), exhaust section (turbine exhaust case (TEC)), and accessory section (main gearbox).
Describe the constructional arrangement and basic operation of a turbojet engine.
A turbojet engine consists of an air inlet, compressor, combustor, turbine, and exhaust. Air is compressed, mixed with fuel, ignited in the combustor, and the high-speed exhaust gases drive the turbine and create thrust.
What are the advantages and disadvantages of a turbojet engine?
Advantages: Simple design, high speeds, compact size. Disadvantages: High fuel consumption, loud, poor performance at low speeds, limited range.
How does a turbofan engine differ from a turbojet engine?
A turbofan engine differs from a turbojet by incorporating a large fan at the front, driven by a low-pressure turbine, which produces about 80% of the thrust, making it more fuel-efficient and quieter.
What are the two types of spool arrangements in turbofan engines, and how do they work?
The two types of spool arrangements in turbofan engines are twin spool and three spool. In a twin spool, one turbine drives the high-pressure compressor, and another drives the low-pressure compressor and fan. In a three spool, there’s an additional intermediate compressor and turbine.
What are the advantages and disadvantages of a turbofan engine?
Advantages: Fuel efficient, quieter than turbojets, streamlined. Disadvantages: Heavier, larger frontal area, inefficient at very high altitudes.
Describe the constructional arrangement and basic operation of a turboprop engine.
A turboprop engine includes a compressor, combustor, turbine, power shaft, and reduction gearbox. It drives a propeller to produce thrust and is designed for efficient mid-range speed and altitude operation.
What are the advantages and disadvantages of a turboprop engine?
Advantages: Very fuel efficient, best at mid-range speeds and altitudes. Disadvantages: Limited forward airspeed, heavy and complex gearing systems.
What is the primary use of a turboshaft engine?
The primary use of a turboshaft engine is to produce shaft power to drive machinery, such as in helicopters or as an Auxiliary Power Unit (APU) in aircraft.
Describe the constructional arrangement and basic operation of a turboshaft engine.
A turboshaft engine operates similarly to a turbojet, with a compressor, combustor, and turbine. However, instead of producing thrust, it drives a shaft to power machinery.
What are the advantages and disadvantages of a turboshaft engine?
Advantages: High power-to-weight ratio, compact size. Disadvantages: Loud, complex and potentially unreliable gear systems.
What is modular engine construction, and what are its benefits?
Modular engine construction divides an engine into replaceable sections (modules) like cold and hot sections. Benefits include easier maintenance, less need for spare parts, and no rebalancing required after module changes.
