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Steam Boilers, Engines, Nozzles And Turbines MCQ
480 Important Steam Boilers, Engines, Nozzles And Turbines MCQ Question and Answer | PDF Free Download
1.In a boiler, the heat is lost
- ATo dry flue gases
- BIn moisture present in the fuel
- CTo steam formed by combustion of hydrogen per kg of fuel
- DAll of the above
2.The friction present between the steam and the nozzle surfaces reduces the heat drop by
- A10 to 15%
- B15 to 25%
- C25 to 40%
- D40 to 60%
3.A valve installed between the boiler and the feed pump is
- ABlow off cock
- BFeed check valve
- CSteam stop valve
- DNone of these
4.The blade friction in the impulse turbine reduces the velocity of steam by __________ while it passes over the blades.
- A10 to 15%
- B15 to 20%
- C20 to 30%
- D30 to 40%
5.The temperature of flue gases at air heater outlet should be
- A100°C
- BAbove dew point temperature of flue gases
- CBelow dew point temperature of flue gases
- DLess than wet bulb temperature of flue gases
6.A compound steam engine in which piston rods of high pressure and low pressure cylinders ' are attached to two different cranks set at 180° to each other, is called
- AReceiver type compound engine
- BTandem type compound engine
- CWoolf type compound engine
- DBoth (A) and (B)
7.A compound steam engine in which piston rods of high pressure and low pressure cylinders are attached to two different cranks set at 90° to each other, is called
- AReceiver type compound engine
- BTandem type compound engine
- CWoolf type compound engine
- DBoth (A) and (B)
8.Water tube boilers are
- AInternally fired
- BExternally fired
- CInternally as well as externally fired
- DNone of these
9.In a nozzle, whole frictional loss is assumed to occur between
- AInlet and throat
- BInlet and outlet
- CThroat and exit
- DAll of these
10.In reaction turbines, the axial thrust is due to
- APressure drop across the rotor
- BChange in axial velocity
- CBoth (A) and (B)
- DNone of these
11.Sublimation region is the region where
- ASolid and vapor phases are in equilibrium
- BSolid and liquid phases are in equilibrium
- CLiquid and vapor phases are in equilibrium
- DSolid, liquid and vapor phases are in equilibrium
12.The diagram factor is the ratio of the
- AArea of the actual indicator diagram to the area of theoretical indicator diagram
- BActual work done per stroke to the theoretical work done per stroke
- CActual mean effective pressure to the theoretical mean effective pressure
- DAny one of the above
13.The overall efficiency of thermal power plant is
- ABoiler efficiency, turbine efficiency, generator efficiency
- BAll the three above plus gas cycle efficiency
- CCarnot cycle efficiency
- DRegenerative cycle efficiency
14.The supersaturated flow of steam through a nozzle as compared to a stable flow, the available heat drop
- ARemains the same
- BIncreases
- CDecreases
- DIs unpredictable
15.The shell of the Cochran boiler is made hemispherical
- ATo give maximum space and strength
- BTo withstand the pressure of steam inside the boiler
- CBoth (A) and (B)
- DNone of the above
16.The value of the reheat factor varies from
- A1.02 to 1.06
- B1.08 to 1.10
- C1.2 to 1.6
- D1.6 to 2
17.The maximum efficiency of a reaction turbine is
- A2 sin²α/(1 + sin²α)
- B2 cos²α/(1 + cos²α)
- C(1 + sin²α)/2 sin²α
- D(1 + cos²α)/2 cos²α
18.An impulse turbine as compared to a reaction turbine, for a given power has _________ row of blades.
- AEqual
- BLess
- CMore
- DNone of these
19.The ratio of the clearance volume to the swept volume is called
- ACut-off ratio
- BExpansion ratio
- CClearance ratio
- DNone of these
20.The ratio of the volume at cut-off to the swept volume is called
- ACut-off ratio
- BExpansion ratio
- CClearance ratio
- DNone of these