Chapter 72- Internal Combustion Engines Flashcards Preview

Power Engineering- 4th Class > Chapter 72- Internal Combustion Engines > Flashcards

Flashcards in Chapter 72- Internal Combustion Engines Deck (67):
1

In a compression engine the fuel is ignited by

The compressed air temperature

2

Diesel engine governing is accomplished by

Varying the fuel quantity

3

Internal combustion engines used to drive gas compression machinery and which burn natural gas operate on the _______ stroke cycle

Two or four

4

How is fuel in a gasoline engine delivered?

An injector
A carburetor

5

What is a fuels resistance to premature detonation called?

Octane rating

6

Four-stroke cycle valves are operated

Cams

7

The purpose of a spark plug

To ignite the air fuel mixture in a gasoline engine

8

An engine which develops one power stroke with every other turn of the crankshaft is the

Four stroke natural gas engine

9

Four cycle engine lubrication may be accomplished by

Pumping oil under pressure

10

An example of a gasoline engine which gives high torque at low speeds would be
A. chainsaw
B. two cycle snowmobile
C. four stroke motor cross motorcycle
D. two cycle lawnmower
E. two cycle transit bus

C

11

A major difficulty encountered with a two-stroke cycle engine is

Exhausting the spent gasses from the cylinder

12

When does the exhaust valve open on a four cycle engine

The end of the power stroke

13

A four stroke ignition engine in theory has ______ the power of a two stroke engine

Half

14

When does the spark plug ignite the air/fuel mixture in a four stroke engine

Near the end of the compression stroke

15

How many ports does a simple two stroke spark ignition engine have?

2

16

Define cylinder scavenging

The removal of exhaust gasses from a cylinder

17

Compression engines

Will compress air only on the compression stroke

18

An injection nozzle is used to _________ the fuel in a Diesel engine

Atomize

19

In larger two stroke Diesel engines how is scavenging air provided

With superchargers

20

The injection pump of a Diesel engine is driven by the

Camshaft

21

Ignition in a Diesel engine is started by

Compression in the cylinder

22

What is a diesels engines camshaft driven by?

The crankshaft

23

How high might the compression ratio of a Diesel engine be

25:1

24

What is the purpose of a pushrods in a typical four stroke Diesel engine?

To operate a rocker arm

25

How might the frame of a Diesel engine be constructed?

Cast or welded

26

Using a compressed air starting motor is a popular method of starting a

Large stationary Diesel engine

27

When using compressed air to each cylinder for starting purposes, the pressure is approximately

2100 Kpa

28

Reduction in sealing qualities between the piston rings and cylinder wall by the lube oil may be a result of

High cooling water temperature

29

Large internal combustion engines achieve cooling by use of

Water jackets

30

In the case of large industrial Diesel engines which is started using compressed air direct to the cylinders, when is the air actually admitted to the cylinders

On the power stroke

31

In which ways might a Diesel engine be started

Hand cranking
Air starter motor
Electric starter
Compressed air delivered to cylinders

32

What must be done before starting a large Diesel engine?

Prime the fuel injector pump

33

What problems could a leaking fuel injector cause in a Diesel engine?

Abnormally high exhaust temperatures
Smoky exhaust

34

VIGV

Variable pitch inlet guide vanes

35

I thermal combustion engines apply to all

Engines burning off fuel

36

Internal combustion changes chemical energy in fuel to

Useful heat

37

What are most common fuels used in an I thermal combustion engine

Natural gas
Gasoline
Light oil fuel
Heavy oil fuel

38

Natural gas is considered

Environmentally clean

39

Natural gas is

Readily accessible

40

Gasoline is

Liquid hydrocarbons enhanced with benzene or Iso-octanes

41

Gasoline is ___ speed type

High

42

The process of vaporization is know as

Carburetion

43

Most modern engines now use

Direct fuel injection

44

Heavy oil fuel is important in what type of combustion engine

High compression engines

45

What are the for steps of a four struck ignition cycle

Intake
Compression
Power
exhaust

46

How is the crankcase lubricated

Pumped under pressure or splashed

47

Two advantages of Four cycle engines

Good fuel economy and good control at all speeds

48

Two stroke ignition cycle had no

Valves or camshaft

49

How is two stroke engine lubricated

My mixing special lubrication with gasoline in the tank

50

In the carburetor the gasoline is

Vaporized

51

Two cycle engines are best for

Max power and min size. Best at high engine speeds

52

In a Diesel engines the fuel is injected at

High pressure directly into the engines cylinder in liquid form (finely atomized)

53

In Diesel engines ignition takes place with out the aid of a

Spark

54

List the four stages of a Diesel engine

Suction
Compression
Power
Exhaust

55

In a two stroke Diesel engine removal is done by

Scavenging

56

What are the most common methods of air induction

Supercharges and turbochargers

57

Diesel engines use what type of ignition

Compression

58

Diesel engines have no

Carburetor

59

What does a carburetor do

Mix air and fuel

60

What are the moving parts in a Diesel engine

Piston
Connecting rods
Crank pins
Crankshaft
Main bearings

61

Diesel engine compression ratio

25:1

62

The fuel for a Diesel engine is

Mechanically atomized by high pressure

63

An example of an engine which gives high torque at low speeds would be that of a

Four stroke engine

64

The purpose of a spark plug is

To ignite the fuel air mixture in a gasoline engine

65

Using a compressed air starting motor is a popular method of starting a

Large stationary Diesel engine

66

When using compressed air to each cylinder for starting purpose the pressure is approximately

2100KPa

67

Reduction in sealing qualities between the piston ring and cylinder wall by the lube oil may be the result of

High cooling water temperatures