The fire tubes in a Cochran boiler are
Horizontal
Vertical
Inclined
None of these
Correct Answer :
A. Horizontal
Related Questions
Degree of reaction is defined as the ratio of
Heat drop in fixed blades to the heat drop in moving blades
Heat drop in moving blades to the heat drop in fixed blades
Heat drop in moving blades to the heat drop in fixed blades plus heat drop in moving blades
Heat drop in fixed blades plus heat drop in moving blades to the heat drop in moving blades
The actual power generated in the engine cylinder is called
Indicated power
Brake power
Frictional power
None of these
Steam turbines may be classified according to
Direction of steam flow
Number of stages
Mode of steam action
All of these
The radius of a dished head is taken approximately as
One fourth
Half
One
Two
Which of the following boiler works on a forced circulation of water?
Lamont boiler
Benson boiler
Loeffler boiler
All of these
The rate of discharge through the nozzle __________ when the exit pressure is gradually reduced.
Remains same
Decreases
Increases
None of these
The impulse reaction turbine has its driving force
As an impulsive force
As a reaction force
Partly as an impulsive force and partly as a reaction force
None of the above
In order to compare the capacity of boilers, the feed water temperature and working pressure are taken as
50°C and normal atmospheric pressure
50°C and 1.1 bar pressure
100°C and normal atmospheric pressure
100°C and 1.1 bar pressure
The ultimate analysis of fuel lists
Various chemical constituents, carbon, hydrogen, oxygen etc, plus ash as percents by volume
Various chemical constituents, carbon, hydrogen, oxygen, etc, plus ash as percents by weight
Fuel constituents as percents by volume of moisture, volatile, fixed carbon and ash
Fuel constituents as percents by weight of moisture, volatile, fixed carbon and ash
The high pressure and low pressure cylinders in a Tandem type compound engine are regarded as having cranks
180° to each other
90° to each other
0° to each other
None of these
In a receiver type compound engine, the high pressure and low pressure cylinders
Have common piston rod
Are set at 90°
Have separate piston rods
Are set in V-arrangement
The air pressure at the fuel bed is reduced below that of atmosphere by means of a fan placed at or near the bottom of the chimney to produce a draught. Such a draught is called
Natural draught
Induced draught
Forced draught
Balanced draught
When the speed of the engine is controlled by means of a valve in a steam pipe, which regulates the pressure of steam entering the engine, then the governing is known as
Throttle governing
Cut-off governing
By-pass governing
None of these
The diameter of fire tube of Cornish boiler compared to its shell is
One half
One third
One fourth
One fifth
An economiser _________ the steam raising capacity of a boiler.
Increases
Decreases
Has no effect on
None of these
In an experiment to determine dryness fraction of steam, the mass of water separated was 1.2 kg in 15 mts. and the mass of steam passed out in same time was 4.8 kg. Dryness fraction is
40 %
25 %
50 %
80 %
The difference between Cornish boiler and Lancashire boiler is that
Former is fire tube type and latter is water tube type boiler
Former is water tube type and latter is fire tube type
Former contains one fire tube and latter contains two fire tubes
None/of the above
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 water tubes in a Babcock and Wilcox boiler are
Horizontal
Vertical
Inclined
Horizontal and inclined
The density of supersaturated steam is about __________ that of the ordinary saturated vapour at the corresponding pressure.
Same as
2 times
4 times
8 times
Water boils when its vapour pressure
Equals that of the surroundings
Equals 760 mm of mercury
Equals to atmospheric pressure
Equals the pressure of water in the container
The shell diameter of a Locomotive boiler is
1 m
1.5 m
2 m
2.5 m
While steam expands in turbines, theoretically the entropy
Remains constant
Increases
Decreases
Behaves unpredictably
The value of diagram factor depends upon
Initial conditions of steam
Back pressure
Initial pressure of steam
All of these
Which of the following statement is correct for a compound steam engine?
The cost of the engine, for the same power and economy, is more than that of a simple steam engine.
The forces in the working parts are increased as the forces are distributed over more parts.
The ratio of expansion is reduced, thus reducing the length of stroke.
The temperature range per cylinder is increased, with corresponding increase in condensation.
The supersaturated flow of steam through a nozzle as compared to a stable flow, the available heat drop
Remains the same
Increases
Decreases
Is unpredictable
The latent heat of steam at pressures greater than atmospheric in comparison to latent heat at atmospheric pressure is
Less
More
Equal
May be less or more depending on temperature
The maximum heat loss is a boiler occurs due to
Moisture in fuel
Dry flue gases
Steam formation
Unburnt carbon
The relative efficiency is defined as the
Ratio of thermal efficiency to Rankine efficiency
Ratio of brake power to the indicated power
Ratio of heat equivalent to indicated power to the energy supplied in steam
Product of thermal efficiency and Rankine efficiency
All steam engines work on
Zeroth law of thermodynamics
First law of thermodynamics
Second law of thermodynamics
None of these