POWERTRAINS - INTERNAL COMBUSTION - Basic Principles

Question 1

What are the four strokes listed in the operating principle?

Answer 1

1. Inlet,
2. Compression,
3. Expansion (POWER),
4. Exhaust.

Question 2

How many crankshaft rotations are needed for one complete four-stroke cycle?

Answer 2

Two rotations of the crankshaft for one complete cycle. (Slide 6)

Question 3

What do TDC and BDC stand for?

Answer 3

TDC: Top Dead Centre (sometimes referred to as Top Centre). BDC: Bottom Dead Centre (sometimes referred to as Bottom Centre). (Slide 6

Question 4

What does the lecture state about engine torque delivery?

Answer 4

Highly Irregular

Question 5

What does the lecture state about mean torque vs maximum torque? FOR single cylinders

Answer 5

Mean torque is much lower than maximum. (Slide 8)

Question 6

What does the flywheel do (as stated on the slide)?

Answer 6

Flywheel stores energy to overcome negative torque.

Question 7

What does the lecture state about multiple cylinders and torque delivery?

Answer 7

Multiple cylinders helps produce smoother torque delivery & higher mean torque. (Slide 8)

Question 8

What does the lecture state about piston motion in an inline four-cylinder engine?

Answer 8

Note two pistons up while two are down – helps balance certain forces and reduce the “shaking” up and down of the engine in the vehicle. (Slide 9)