Short delay period
Late auto-ignition
Low compression ratio
High self ignition temperature of fuel
A. Short delay period
Opens at 50° before bottom dead centre and closes at 15° after top dead centre
Opens at bottom dead centre and closes at top dead centre
Opens at 50° after bottom dead centre and closes at 15° before top dead centre
May open and close anywhere
Minimum turbulence
Low compression ratio
High thermal efficiency and power output
Low volumetric efficiency
20 to 40
40 to 60
60 to 80
80 to 100
Leaking piston rings
Use of thick head gasket
Clogged air inlet slots
All of the above
Cetane number
Octane number
Calorific value
None of these
Enhance flow rate
Control air flow
Induce primary swirl
Induce secondary turbulence
Spark ignition
Compression ignition
Both (A) and (B)
None of these
Decreasing the density of intake air
Increasing the temperature of intake air
Increasing the pressure of intake air
Decreasing the pressure of intake air
Iso-octane and alpha-methyl naphthalene
Normal octane and aniline
Isooctane and normal hexane
Normal heptane and isooctane
Higher maximum temperature
Qualitative governing
Quantitative governing
Hit and miss governing
F.P. = B.P. - I.P.
F.P. = I.P. - B.P.
F.P. = B.P./I.P.
F.P. = I.P./B.P.
Minimum temperature to which oil is heated in order to give off inflammable vapours in sufficient quantity to ignite momentarily when brought in contact with a flame
Temperature at which it solidifies or congeals
It catches fire without external aid
Indicated by 90% distillation temperature, i.e., when 90% of sample oil has distilled off
Homogeneous
Heterogeneous
Both (A) and (B)
None of these
30° before top dead centre
30° after top dead centre
30° before bottom dead centre
30° after bottom dead centre
1 : 1
5 : 1
10 : 1
15 : 1
The ratio of volumes of air in cylinder before compression stroke and after compression stroke
Volume displaced by piston per stroke and clearance volume in cylinder
Ratio of pressure after compression and before compression
Swept volume/cylinder volume
Fuel injection starts at 10° before to dead center and ends at 20° after tor dead center
Fuel injection starts at top dead center and ends at 20° after top dead center
Fuel injection starts at just before top dead center and ends just after top dead center
May start and end anywhere
15 %
30 %
50 %
70 %
Starts at 15° before top dead centre and ends at 30° after top dead centre
Starts at top dead centre and ends at 30° after top dead centre
Starts at 15° after top dead centre and ends at 30° before bottom dead centre
May start and end anywhere
Opens at 20° before top dead centre and closes at 40° after bottom dead centre
Opens at 20° after top dead centre and closes at 20° before bottom dead centre
Opens at top dead centre and closes at bottom dead centre
May open and close anywhere
To reduce mass of the engine per brake power
To reduce space occupied by the engine
To increase the power output of an engine when greater power is required
All of the above
[2(V₀/V₁)]/ [1 + (V₀/V₁)²]
(V₀/V₁)/ [1 + (V₀/V₁)²]
V₀/(V₀ + V₁)
V₁/(V₀ + V₁)
High heat value
Low heat value
Net calorific value
Calorific value
Pre-ignition period
Delay period
Period of ignition
Burning period
0
50
100
120
kcal
kcal/kg
kcal/m²
kcal/m3
6 to 10
10 to 15
15 to 25
25 to 40
Opens at top dead centre and closes at bottom dead centre
Opens at 20° before top dead centre and closes at 40° after bottom dead centre
Opens at 20° after top dead centre and closes at 20° before bottom dead centre
May open or close anywhere
30 kW four-stroke petrol engine running at 1500 r.p.m.
30 kW two-stroke petrol engine running at 1500 r.p.m.
30 kW two-stroke diesel engine running at 750 r.p.m.
30 kW four-stroke diesel engine running at 750 r.p.m.
Temperature and pressure in the cylinder at the time of injection
Nature of the fuel mixture strength
Relative velocity between the fuel injection and air turbulence pressure of residual gases
All of the above