M15.1 Flashcards
Newton’s first law
Law of inertia
A body at rest remains at rest and a body in motion continues to move at a constant velocity unless acted upon by an unbalanced external force.
Kinetic energy equation
Kinetic Energy (KE) =.
È × Mass (m) × Velocity (22)
Potential energy equation
Mgy
What is potential energy
Energy stored when a body is at rest
What are the 2 types of energy
- Potential
- Kinetic
Newton’s second law
That the acceleration produced in a mass by a force acting on it is directly proportional to the force and inversely proportional to the mass.
Force = Mass x Acceleration
Newtons 3rd law
Every action has an equal and opposite reaction. This means that no matter what the circumstances, when one object exerts a force on a second object, the second must exert an equal and oppositely directed force on the first
What is energy defined as
Something that gives us capacity to do work
What is the brayton cycle
The Brayton cycle is the name given to the thermodynamic cycle of a gas turbine engine that produces thrust.
What are the 4 stages of the brayton cycle
This has four stages: intake (suck), compression (squeeze), expansion (bang), and exhaust (blow).
Acceleration due to gravity
9.81m/s squared
Engine cycle
Induction
Compression
Combustion
Exhaust
Isobaric heating
Increase in temperature at constant pressure
Isobaric
Constant pressure
Isochoric
Constant volume
Isothermal
Constant temperature
Isentropic
Adiabatic and reversible
What changes of state are important for gas turbine engines
Isobaric and isentropic
Two types of aircraft engines
Piston type
Gas turbine
Piston engine advantages
Fuel efficiency
Piston engine disadvantages
High power to weight ratio
Performance loss at high altitudes
Types of gas turbine engines
- Turbojet
- Turbofan
- Turboprop
- APU
What is an engine that uses jet propulsion called
Reaction engine
Parameters that determine thrust
Mass of ambient air
Amount of acceleration
Four main environmental parameters that effect thrust
- Ambient air pressure
- Air temp
- Altitude
- Air speed
At what altitude does ambient temperature and pressure stop decreasing
36000 feet
Temp between 36000 and 57000 ft
-57c
What engine uses 20% less fuel than high bypass engines
Prop fans
Engine construction principles
Modular
Non modular
Advantages of modular design for manufacturers
- Rotating modules can be pre balanced
- Less spare engines
- Flexibiity to change individual parts
- Easy storage and transport
Advantages of modular designs for operators
- Modules can be easily removed
- No re-balanced after replacement
- On wing changes
- Less spares
What is used to make N1 shaft
Steel alloy
What is titanium based alloys used to build
Fan
HPC
What is cobalt base alloy used to build
Turbine nozzle
What is nickel based alloys used to build
HPT
LPT
