Alpha
Heat engines use _______________ energy and convert it into ________________ energy and then into _____________ energy
What is chemical; heat/thermal; mechanical
Instead of spark plugs, this engine uses _______________ for ignition.
What is diesel engine
What are glow plugs?
What is they are essentially resistors that heat up and start to glow, which help diesel engines ignite fuel and air when temperatures are cold, and to assist with starting in general.
What kind of turbine engine does not use bypass air?
What is Turbojet
The "360" in IO-360-L2A indicates what?
What is the average mechanical efficiency of an aircraft recip engine?
What is 90%
The swept volume of all the pistons inside the cylinders of a reciprocating engine in a single movement from top dead center (TDC) to bottom dead center (BDC).
What is engine displacement
This type of efficiency is the ratio between the theoretical amount of air that could be displaced by pistons, vs the actual amount of air (mass density) being displaced by the pistons. This is primarily affected by our environment - air density, temperature, altitude, etc...
What is volumetric efficiency
The ratio of air that is routed through a turbine engine to the air routed around a turbine engine is called:
What is bypass ratio
What is 34% (I will accept 25-35%)
Diesel engines have a higher _________________ ratio than reciprocating engines.
What is Compression Ratio
The term used for an engine that takes it's air from the ambient atmosphere is called a:
Hint: (Our training aircraft engines are this)
What is normally aspirated engine
The amount of force a piston places on the crankshaft at any given RPM is a measure of:
Hint: Measured in lbs-ft. Think of the size of stroke; if a piston has a longer stroke, it has a longer piston rod, and provides for a greater throw on the crankshaft.
What is torque
A manifold pressure gauge measures:
What is brake horsepower
This air is taken from the engine and used for things like pressurization and heating the leading edges of the engine nacelle. What is this air referred to as?
What is bleed air
What part of a reciprocating engine does the primary mechanical work?
This slows the air down after going through the high pressure compressor stages before it is fed into the combustor
What is diffuser
How do turbine engines convert heat energy into mechanical energy?
What is the expanding air from combustion is forced through a series of turbines, which force a shaft to rotate.
Even better, the shaft is either connected to a compressor section, a compressor section and fan, or a gearbox that powers a propeller, or another geared shaft that powers a helicopter
Why are some exhaust cowlings on turbofans serrated?
What is noise reduction
Turbofans use this type of compressor:
What is co-axial compressor
Where is bleed air typically taken from?
What is The high pressure stages of the compressor section
Turboprops usually use this type of compressor:
What is centrifugal compressor
What percentage of thrust comes from the bypass air on a high bypass turbofan engine?
What is 70-80%
Modern high bypass turbofans use this type of combustor
What is annular