Fundamentals Flashcards
What is “g”?
Acceleration due to gravity
Which law is Newton’s law of inertia?
1st
What are the two forms of mechanical energy?
Potential energy
Kinetic energy
What is the unit and equation for kinetic energy?
Joules (J)
E=1/2mv^2
What is the working fluid of the gas turbine engine?
Air
What is heating at constant pressure called?
Isobaric heating
Which is the most fuel efficient engine at low altitude?
Turboprop
What is always required on a turboprop?
Reduction gearbox
What produces the most thrust on a turbo fan?
The fan
Turbofan engines are normally of what configuration?
Double or triple spool.
What type of construction are modern engines?
Turbofan
What types of engines were developed from the turbojet engine?
Turbofan
Turboprop
What qualities should engine materials have?
Light
Cheap
Strong enough for its task
What are the turbine blades made from?
Titanium
What is Newton’s 3rd law and what is it known as?
Every action has an equal and opposite reaction.
Law of action and reaction
What is Newton’s first law of motion?
An object is at rest or constant motion unless the forces acting upon it become unbalanced.
What is the unit and equation for force?
Newtons (N)
F=ma
What is the unit and equation for work?
Joules (J)
Work= force x distance
What is the unit and equation for power?
Watts (W)
Power= work/time
What is the unit and equation for potential energy?
Joules (J)
E=mgh
What does an engine provide for the aircraft?
Thrust
Hydraulics
Electrics
Pneumatics
What is the Brayton cycle for a gas turbine engine?
Compression
Combustion
Exhaust
What is the difference between the Brayton cycle and a reciprocating engine?
The Brayton cycle is happening all at once in a continuous motion and run of the engine, while the piston engine has to complete each stage individually.
How does a turboprop generate thrust?
Small acceleration of a large quantity of air.
How does a turbo-jet produce thrust?
High acceleration of a small quantity of air
How does the turbofan generate thrust?
Fan- small acceleration of a large quantity of air.
Core engine- high acceleration of a small quantity of air
The two then combine at the exhaust to create the overall thrust.
What is the bypass ratio?
The amount of air that bypasses the combustion chamber.
What are the major engine modules?
Fan
Core
Accessory drive
Low pressure turbine
What parts of the engine are made of aluminium?
Fan case
Gearbox
Fan exit case
What is the fan module made of?
Aluminium
Where are ceramics used on the engine?
Combustor
High pressure turbine
What is the drive shaft and bearings made of?
Steel
What is the only part made of cobalt?
Turbine nozzle
What is the advantage of titanium and where it is fitted?
It has the same strength as steel at half the weight.
It is fitted in the fan, HP compressor, and LP compressor.
Which type of engine generates the most thrust?
Turbofan
