M15.1 Flashcards
What is energy
Something that gives us the capacity to perform work
2 types of energy
Potential and kinetic
Calculation for potential energy
PE = mgh
Calculation for kinetic energy
KE = 1/2 x m x v2
What is Newton’s first law
Law of inertia, remains at rest/in motion unless acted upon by a force
What is newtons 2nd law
Force = ma
What is newtons 3rd law
Law of action and reaction
What is Brayton cycle
Thermodynamic cycle of a GTE that produce thrust
4 stages of brayton cycle
Intake (suck)
Compression (squeeze)
Expansion (bang)
Exhaust (bang)
What is a GTE
Gas turbine engine is a heat engine that uses air as a working fluid to provide thrust
What are thermal processes called and what are they cause by
Changes of state, caused by heat, cooling, expansion or compression
What are thermal processes called
Changes of state
What are the 4 changes of state
Isobaric, isochoric, isothermal and isentropic
Isobaric and isentropic are most important
How are changes of state represented
Pressure- volume diagram (PV)
What is force measured in
Lb or N
1lb = 4.448N
What is work
Done when a force is moved through a distance in direction of force. Measure of energy transferred.
Calculation for work
Work = force x distance
1J = 1Nm
What is power
How long is takes to accomplish work
Calculation for power
Power = work/time
1W = 1Nm/s
What is motion
Continuing change of position/place
What is speed
How fast an object is moving or how fair it will travel in a specific time
What is velocity
Vector quantity that describes speed and direction of object
What is acceleration
Rate of change of velocity
Calculation for acceleration
Change in velocity/time = m/s2
What is the main function of engine
Provide necessary movements of ac and supply hydraulic and electrical power and bleed air
What are the types of gas turbine engine
Turbojet, turbofan, turboprop and turboshaft
What is a turbojet engine
First type, high speeds but very loud
Problems with noise and fuel consumption at 0.8 mach
What is turbofan
Most common, high speed, efficient, 80% thrust, large fan at the front
What is turboprop
Produce shaft horsepower only to drive a propeller
What is turboshaft
Produces shaft power to drive machinery instead of thrust. Used in applications that require small, powerful, lightweight engine (APU)
What happens with reciprocating engine compared to GTE
Reciprocating - intake, compression, combustion and exhaust all take place in combustion chamber
Whereas in GTE they all have separate sections to perform different functions
What is cold section
Part of engine from inlet to compressor
What is hot section
Combustion to exhaust
What is hot section
Combustion to exhaust
