The maximum discharge of steam through a convergent-divergent nozzle depends upon
Area of nozzle at throat
Initial pressure and volume of steam
Final pressure of steam leaving the nozzle
Both (A) and (B)
Correct Answer :
D. Both (A) and (B)
Related Questions
The fire tubes in a Cochran boiler usually have _________ diameter.
6.25 mm
62.5 mm
72.5 mm
92.5 mm
By compounding the expansion of steam in two or more cylinders, the length of stroke
Does not change
Increases
Decreases
None of these
The major axis of elliptical manholes on the shell should be provided
Longitudinally
Circumferentially
On dished end
Anywhere
The fire tubes in, a Coarran and Scottish marine boiler are
Horizontal
Vertical
Inclined
Both horizontal and vertical
Pick up the wrong statement about water tube boiler in comparison to fire tube boilers
Former occupies less space for same power
Rate of steam flow is more in former case
Former is used for high installed capacity
Chances of explosion are less in former case.
In a single acting steam engine
The steam is admitted on one side of the piston and one working stroke is produced during each revolution of the crankshaft
The steam is admitted, in turn, on both sides of the piston and one working stroke is produced during each revolution of the crankshaft
The steam is admitted on one side of the piston and two working strokes are produced during each revolution of the crankshaft
The steam is admitted, in turn, on both sides of the piston and two working strokes are produced during each revolution of the crankshaft
The actual vacuum in a condenser is equal to
Barometric pressure + actual pressure
Barometric pressure - actual pressure
Gauge pressure + atmospheric pressure
Gauge pressure - atmospheric pressure
In regenerative air preheaters, the heat is transferred
From a metal wall from one medium to another
From heating an intermediate material and then heating the air from this material
By direct mixing
Heat is transferred by bleeding some gas from furnace
The length of Cornish boiler is of the order of
24 m
35 m
57.5 m
79 m
Expansion ratio is the ratio of
Swept volume to the volume at cut-off
Clearance volume to the swept volume
Volume at cut-off to the swept volume
Swept volume to the clearance volume
The selection of type and size of a steam boiler depends upon
The power required and working pressure
The geographical position of the power house
The fuel and water available
All of the above
The radius of a dished head is taken approximately as
One fourth
Half
One
Two
In locomotive boiler, maximum steam pressure is limited to
1 kg/cm²
5 kg/cm²
10 kg/cm²
18 kg/cm²
Fire tube boilers are those in which
Flue gases pass through tubes and water around it
Water passes through the tubes and flue gases around it
Forced circulation takes place
Tubes are laid vertically
Sublimation region is the region where
Solid and vapour phases are in equilibrium
Solid and liquid phases are in equilibrium
Liquid and vapour phases are in equilibrium
Solid, liquid and vapour phases are in equilibrium
The object of producing draught in a boiler is
To provide an adequate supply of air for the fuel combustion
To exhaust the gases of combustion from the combustion chamber
To discharge the gases of combustion to the atmosphere through the chimney
All of the above
Heating of dry steam above saturation temperature is known as
Enthalpy
Superheating
Super saturation
Latent heat
The flow through a nozzle is regarded as
Constant volume flow
Constant pressure flow
Isothermal flow
Isentropic flow
Which of the following substance will have same percentage in both proximate and ultimate analysis?
Ash
Volatile matter
Moisture
Hydrogen
The discharge is __________ at critical pressure.
Zero
Minimum
Maximum
None of these
The crown of the fire box is made hemispherical in order to
Give maximum space
Give maximum strength
Withstand pressure inside boiler
Resist intense heat in fire box
The clearance in the engine cylinder
Increases the mean effective pressure
Increases the workdone
Decreases the efficiency of the engine
All of these
O₂ content in atmospheric air on volume basis is
21 %
23 %
30 %
40 %
The diameter of Cornish boiler varies from
0.5 to 1 m
1 to 2 m
1.25 to 2.5 m
2 to 3 m
Locomotive type' boiler is
Horizontal multi-tubular water tube boiler
Water wall enclosed furnace type
Vertical tubular fire tube type
Horizontal multi-tubular fire tube type
Alkaline pyrogallate is used in Orsat's apparatus for absorption of
CO₂
CO
O₂
N₂
The friction in the nozzle __________ exit velocity of steam.
Has no effect on
Decreases
Increases
None of these
The shell of the Cochran boiler is made hemispherical
To give maximum space and strength
To withstand the pressure of steam inside the boiler
Both (A) and (B)
None of the above
A regenerative steam cycle renders
Increased work output per unit mass of steam
Decreased work output per unit mass of steam
Increased thermal efficiency
Decreased work output per unit mass of steam as well as increased thermal efficiency
The maximum steam pressure in a Locomotive boiler is limited to
0.18 MN/m²
1.8 MN/m²
18 MN/m²
180 MN/m²