190201a Engine Fundamentals

Question 1

how many years ago was the first internal combustion developed

Answer 1

200

Question 2

internal combustion engines convert heat energy of fuel into

Answer 2

useable mechanical energy and wasted heat

Question 3

the term compression ignition refers to

Answer 3

the method of igniting fuel in a diesel engine

Question 4

the term torque could best be described as a

Answer 4

rotational force

Question 5

what is the swept volume of a single cylinder referred to as?

Answer 5

piston displacement

Question 6

the compression ratio would be about _______ times that of a gas engine

Answer 6

2 times

Question 7

a dirty air filter would do what to the Volumetric efficiency of an engine

Answer 7

decrease it

Question 8

horsepower is a measurement of

Answer 8

the rate of doing work

Question 9

What is the general rule of thumb for engine thermal efficiency

Answer 9

1/3 work 1/3 cooling 1/3 lost to exhaust

Question 10

the term stroke refers to

Answer 10

distance piston moves from TDC to BDC

Question 11

scavenging is a term that refers to

Answer 11

removing exhaust gases from the cylinder

Question 12

what is the term for the degrees that intake and exhaust valves are open/

Answer 12

valve overlap

Question 13

rpm and fuel output are controlled on a diesel by

Answer 13

regulating fuel quantity

Question 14

cam on a 4 stroke rotates at _________ crankshaft speed?

Answer 14

1/2

Question 15

main purpose of a turbocharger is to increase _______?

Answer 15

volumetric Efficiency

Question 16

area = bore squared x 0.7854 or ?

Answer 16

A = π x r squared

Question 17

you calculate piston displacement by what formula

Answer 17

area X stroke

Question 18

amount of air taken into a cylinder during the intake stroke divided by the actual volume is known as?

Answer 18

volumetric efficiency (expressed in a percentage)

Question 19

1 BTU = ___________ kj.

Answer 19

1.055 Kj

Question 20

1 hp = __________watts.

Answer 20

746 watts

Question 21

the bore of the engine refers to the

Answer 21

diameter of the cylinder
Imperial inches (in)
S.I. (metric) millimeters (mm) or centimeters (cm)

Question 22

what is meant by a naturally aspirated induction system?

Answer 22

outside air pressure is used to fill the cylinder

Question 23

the ability of an engine to convert the heat energy of the fuel to usable heat energy to push the piston is known as?

Answer 23

Thermal efficiency

Question 24

the stroke of an engine is

Answer 24

twice the throw

Question 25

What are the three types of horsepower

Answer 25

1. indicated (ihp)
2. frictional (fhp)
3. brake horsepower (bhp)
   bhp = ihp - fhp

Question 26

as soon as the exhaust valve opens and release pressure is called

Answer 26

blow down

Question 27

blower scavenging on a two stroke engine requires

Answer 27

a positive displacement air pump

Question 28

maximum pressure is obtained at approximately _______ after TDC

Answer 28

23 degrees

Question 29

on power stroke at what degree is maximum pressure obtained approximately?

Answer 29

20 - 25 degrees

Question 30

what are the two different ways to cool the intake air on a diesel engine?

Answer 30

Intercooled (air to air)

Aftercooled (air to coolant)

Question 31

the effective power stroke of a two stroke cycle engine is limited to approximately ____ to ____of crankshaft rotation.

Answer 31

90 t0 95 degrees

Question 32

the effective power stroke of a four stroke cycle engine is limited to approximately ____ to ____of crankshaft rotation.

Answer 32

120 to 140 degrees

Question 33

in order for a two stroke cycle diesel engine to scavenge, the must have?

Answer 33

positive inlet pressure

Question 34

internal combustion engine dissipates approximately 60% of the heat developed by combustion through?

Answer 34

cooling and exhaust systems

Question 35

what are the three types of horse power?

Answer 35

indicated horsepower
frictional horsepower
brake horsepower (bhp = ihp - fhp)

Question 36

compression ratio of a gas engine?

Answer 36

8:1 to 9:1

Question 37

compression ration of a diesel engine?

Answer 37

14:1 to 23:1

Question 38

as soon as the exhaust valve opens and exhaust pressure is released in a two stroke cycle diesel, is called?

Answer 38

blow down

Question 39

the term stroke refers to?

Answer 39

the distance a piston travels from TDC to BDC

Question 40

the ability of a diesel engine to convert the heat energy if the fuel into useable heat energy to push the piston down.

Answer 40

thermal efficiency

Question 41

what does naturally aspirated mean?

Answer 41

air enters the inlet manifold under atmospheric pressure

Question 42

what is scavenging?

Answer 42

the removal of exhaust gas from the cylinder