AGK - Piston Engine Principles Flashcards
What is the formula for power, in relations to piston engine power?
Power = Torque x RPM
What is the 4 stroke cycle?
It is:
- Induction
- Compression
- Power
- Exhaust
What happens to the inlet valve at the induction stroke?
The inlet valve opens to allow the charge of air in.
What happens at the compression stroke?
The inlet and exhaust valve are closed, and the piston moves up towards the TDC (Top Dead Centre).
What happens at the power stroke?
The inlet and exhaust valves are still closed, and the piston moves down to the BDC (bottom dead centre).
What happens at the exhaust stroke?
The exhaust valve opens, and the piston moves back up to the TDC (top dead centre).
What is the valve lead?
The valve lead is when the inlet valve opens just before the piston reaches TDC at the end of the exhaust stroke.
What is valve lag?
The inlet valve remains open after the piston starts the compression stroke.
What is exhaust valve lead and lag?
Exhaust valve is opened just before the end of the power stroke.
What is the valve overlap?
It is when both inlet and exhaust valves are open at the end of the exhaust stroke, and at the start of the induction stroke - this is known as the Valve Overlap.
What is an advantage of Lead and Lag?
Reduces speed of which the Valves have to work, which reduces stress on the gear.
What is Ignition Timing?
It is when the ignition is timed to occur just before the top dead centre on the compression stroke.
What does the crankshaft do?
It converts linear motion into rotary motion.
