Diesel engines

Question 1

What is the principle of Diesel engines?

Answer 1

A diesel engine takes in air,compresses it and then injects fuel into the compressed air.The heat of the compressed air ignites the fuel spontaneously

Question 2

What are Diesel engines used for?

Answer 2

Prime mover for Diesel generators. The engine is connected via a drive shaft

Question 3

4 Stroke cycle

Answer 3

1. Induction
2. Compression
3. Power
4. Exhaust

Question 4

Why is it called the 4 stroke cycle?

Answer 4

Operating cycle of the engine is 2 up & 2 down strokes of the piston.

Question 5

Describe the induction stoke

Answer 5

• Inlet valve opens to allow air into cylinder
• At the same time the exhaust valve closes
• Piston moves from TDC to BDC,creating a depression that draws in the air

Question 6

Describe the Compression stroke

Answer 6

• Piston moves from BDC to TDC
• The valves are shut,increasing pressure which heat up the air
• Towards the top of the stroke,atomised fuel is injected

Question 7

Describe the Power stroke

Answer 7

• the atomised fuel ignites
• Piston reaches the TDC
• The combusting gases create pressure,forcing the piston to BDC

Question 8

Describe Exhaust stroke

Answer 8

• The exhaust valve opens shortly before BDC
• The remaing pressure forces the exhaust gases through the exhaust valve
• Piston goes from BDC to TDC facing out the remaing exhaust gases