Q1 Piston Engines Basic Principles & Construction Flashcards
Which of the following statements is correct?
Select one:
1.The Bore is the area of the Piston and Rings and the Stroke is from TDC to BDC.
2.The Bore x Swept Volume = Total Volume.
3.A Stroke is two Throws and is from TDC to the top of the cylinder.
4.The Bore is the Total Volume less Clearance Volume and the Stroke is the throw.
1.The Bore is the area of the Piston and Rings and the Stroke is from TDC to BDC.
Ignition timing is crucial to petrol piston engines. When is ignition timing generally needed to be advanced and retarded?
Select one:
1.Ignition timing is never changed on aircraft piston engines.
2.Unless overrevving the engine there is no need to change the ignition timing.
3.It is retarded as engine RPM increases and advanced for starting.
4.It is advanced as engine RPM increases and retarded for starting.
4.It is advanced as engine RPM increases and retarded for starting.
Piston Engines only work because of the combined gas laws. Which components of the combined gas law are not constant during combustion?
a.T, V
b.P, V
c.T only
d.P, T
d.P, T
𝑃𝑉÷𝑇 is the Combined Gas Law.
In the practical four stroke cycle, How many times does each of the valves in a cylinder open and what is responsible for this?
Select one:
1.Once per cycle, by the Crankshaft.
2.Twice per cycle, by the rocker gear.
3.Once per cycle, by the Camshaft.
4.Twice per cycle, by the Camshaft
3.Once per cycle, by the Camshaft.
Which of the following statements about a piston engine are correct or incorrect?
1.The combustion process in a piston engine is continuous
2.Theoretically, combustion occurs at a constant pressure
Select one:
a.1) is incorrect, 2) is incorrect
b.1) is correct, 2) is incorrect
c.1) is incorrect, 2) is correct
d.1) is correct, 2) is correct
a.1) is incorrect, 2) is incorrect
Explain the purpose of inlet valve lead and exhaust valve lag in the practical four stroke cycle?
Select one:
a.Because otherwise it would be a rotary engine.
b.To decrease volumetric efficiency and increase power due to combustion being a timed finite event.
c.Because the valves cannot overlap
d.To take advantage of ineffective crank angle and increase volumetric efficiency.
d.To take advantage of ineffective crank angle and increase volumetric efficiency.
What is the meaning of the term ‘thermal efficiency’ when applied to an aircraft engine?
Select one:
1.The Cylinder Head Temperature at start, compared to the final running temperature.
2.The CHT/EGT
3.The relationship between the heat energy converted into power output compared to the maximum potential heat energy in the fuel consumed.
4.The Temperature required to give a stable flame continuity.
3.The relationship between the heat energy converted into power output compared to the maximum potential heat energy in the fuel consumed.
What engine layout is described as having two rows of cylinders at an angle of less than 90° to each other connected to a common crankshaft, which gives a shorter more rigid engine?
Select one:
1.Radial.
2.V arrangement.
3.Horizontally opposed.
4.Inline.
2.V arrangement.
The Crankshaft Assembly consists of what components?
Select one:
a.The Crankshaft, Connecting Rods, Camshaft and attaching parts.
b.The Camshaft, Connecting Rods, Pistons and Rings and attaching parts.
c.The Crankshaft, Connecting Rods, Pistons and Rings and attaching parts.
d.The Crankshaft, pistons and Valve Gear.
c.The Crankshaft, Connecting Rods, Pistons and Rings and attaching parts.
Which of the following orders of the continuous 4-Stroke cycle is correct?
Select one:
1.Power, Exhaust, Induction, Compression.
2.Compression, Power, Induction, Exhaust.
3.Exhaust, Induction, Power, Compression.
4.Induction, Power, Compression, Exhaust.
1.Power, Exhaust, Induction, Compression.
What is meant by the term ‘Mechanical Efficiency’?
Select one:
1.The Ratio of Theoretical Power/ Friction Power.
2.The Ratio of the work done at the Propeller/The work done + work wasted.
3.How easily the engine can be started and run using a starter motor.
4.The volume of fuel and air required to maintain take off power.
2.The Ratio of the work done at the Propeller/The work done + work wasted.
The part of a piston engine that converts the reciprocating motion of the Pistons into rotary motion is the:
a.Connecting Rod
b.Camshaft
c.Crankshaft
d.Gudgeon Pin
c.Crankshaft
What is the working cycle of the petrol piston four stroke cycle?
Select one:
1.Compression, Induction, Power, Exhaust.
2.Induction, Compression, Power And Exhaust.
3.Power, Exhaust, Induction, Compassion.
4.Induction, Compression, Combustion, Power.
2.Induction, Compression, Power And Exhaust.
In the practical four stroke cycle, what term is applied to the period when both the inlet valve and the exhaust valve are open at the same time, and when does this occur?
Select one:
1.Valve Overlap, between the Exhaust and Induction strokes.
2.Valve Lag, between the induction and compression strokes.
3.Valve Overlap, between the Exhaust and Power strokes.
4.Valve Lead, between the Exhaust and Induction strokes.
1.Valve Overlap, between the Exhaust and Induction strokes.
Define ‘ineffective crank angle’?
Select one:
1.The angle outside of which the engine is unable to rotate fast enough for engine start.
2.When for the same angular rotation of the crankshaft, the Piston moves more linearly.
3.When for the same angular rotation of the crankshaft, the Piston only moves a little linearly.
4.The period between strokes when the engine is ineffective.
3.When for the same angular rotation of the crankshaft, the Piston only moves a little linearly.
