Thermal Rev 1

Air standard Otto cycle : compression ratio : 8, Efficiency ?

• 60

• 28.2

• 56.4

• 45

lean mixture means

• Less density mixutre

• actual A/F = Stoichiometric A/F

• actual A/F > Stoichiometric A/F

• actual A/F < Stoichiometric A/F

Stages of combustion in Diesel Engine

• Controlled combustion,Delay phase, uncontrolled combustion, after buring

• Delay phase, controlled combustion, uncontrolled combustion, after buring

• Delay phase, uncontrolled combustion, controlled combustion, after buring

• Controlled combustion, uncontrolled combustion, After buring,Delay phase,

In actual SI engine valve timing diagram inlet valve opens and closes (appx) at --- and --- respectively.

• 35 degree before BDC, 10 degree after TDC

• 50 degree before TDC , 35 degree after BDC

• 20 degree before TDC , 35 degree after BDC

• 20 degree before TDC , 60 degree after BDC

In actual SI engine valve timing diagram spark ignition done at ---.

• TDC

• 1 degree before TDC

• 35 degree before TDC

• 60 degree after BDC

In a reciprocating engine with a cylinder diameter of D and stroke of L, the cylinder volume is

• (pi/4.D²L) / clearance volume

• (pi/4.D²L) - clearance volume

• (pi/4.D²L) + clearance volume

• (pi/4.D²L) * clearance volume

4-stroke diesel engine has a displacement volume of 25.9 litres. Engine output power 950 kW @ 2200 rpm. MEP in MPa is

• 1

• 0.2

• 2

• 0.1

Air standard Otto cycle: The clearance volume is 10% of the swept volume. Air standard cycle efficiency?

• 60.2

• 39.8

• 61.7

• 38.3

IC engine gives an output of 3kW when the input is 10000 J/s. Efficiency in percentage?

• 33.33

• 0.33

• 30

• 0.3

Otto cycle: Compression ratio= 5.5 ,work output per cycle is (2362500 * clearance volume). Indicated MEP in bar

• 86.87

• 4.29

• 5.25

• 106.3