⚙️Mechanical Engineering MCQs
Mechanical Engineering MCQs
488 MCQs451
For the same diameter and thickness of tube, a water tube boiler compared to a fire tube boiler has ____________________?
Amore heating surface
Bless heating surface
Cequal heating surface
Dheating surface depends on other parameters E. none of the above
452
The size of a boiler drum in pulverised fuel fired boiler,as its size and capacity, (steam pressure and flow ratings) increase __________________?
Aincreases
Bdecreases
Cremains unchanged
Dincreases/decreases depending on steam temperature requirements E. unpredictable
453
Green coal, in order to be burnt, must be____________________?
Aheated sufficiently
Bburnt in excess air
Cheated to its ignition point
Dburnt as powder E. burnt as lumps
454
The proximate analysis of fuel lists__________________?
Avarious chemical constituents, carbon, hydrogen, oxygen etc, plus ash as per-cents by volume
Bvarious chemical constituents, carbon, hydrogen, oxygen, etc, plus ash as per-cents by weight
Cfuel constituents as percents by volume of moisture, volatile, fixed carbon and ash
Dfuel constituents as percents by weight of moisture, volatile, fixed carbon and ash E. moisture and ash free heating value
455
The safety valve on boiler drum compared to safety valve on super heater is set at ________________?
Asame value
Bhigher value
Clower value
Dlower/higher depending on steam flow E. unpredicatble
456
The three “Ts” for good combustion are____________________?
Atemperature, time, and turbulance
Btotal air, true fuel, and turbulance
Cthorough mixing, total air, and temperature
Dtotal air, time, and temperature E. none of the above
457
Gardually increasing temperature of flue gases at inlet to chimney for given steam outputs is an indication of__________________?
Ahigher effectiveness of boiler
Bhigh calorific value coal being burnt
Cfouling of heat transfer surfaces
Draising of steam temperature E. leakage of air
458
The capacity of induced draft fan compared to forced draft fan in a boiler is__________________?
Asame
Bmore
Cless
Dless or more depending on size of boiler E. unpredictable
459
Feed water conditioning in thermal power plants in done to__________________?
Areduce hardness and for removal of solids
Bincrease efficiency-of thermal power plant
Cincrease *heat transfer rate
Dincrease steam parameters E. all of the above
460
Boiler parameters are expressed by ___________________?
Atonnes/hr. of steam
Bpressure of steam in kg/cm2
Ctemperature of steam in °C
Dall of the above E. none of the above