Presence of moisture in fuel oil would
Keep the burner tips cool
Aid in proper combustion
Because sputtering, possibly extinguishing flame
Clean the nozzles
Correct Answer :
C. Because sputtering, possibly extinguishing flame
Related Questions
The length of Cornish boiler is of the order of
24 m
35 m
57.5 m
79 m
The amount of water evaporated in kg per kg of fuel burnt is called
Evaporative capacity of a boiler
Equivalent evaporation from and at 100° C
Boiler efficiency
None of these
In a nozzle, whole frictional loss is assumed to occur between
Inlet and throat
Inlet and outlet
Throat and exit
All of these
Rateau turbine is
Simple reaction turbine
Velocity compounded turbine
Pressure compounded turbine
Pressure-velocity compounded turbine
For the same diameter and thickness of tube, a water tube boiler has ________ heating surface as compared to fire tube boiler.
More
Less
Equal
None of these
By compounding the expansion of steam in two or more cylinders, the length of stroke
Does not change
Increases
Decreases
None of these
Superheating of steam is done at
Constant volume
Constant temperature
Constant pressure
Constant entropy
An economiser in a boiler
Increases steam pressure
Increases steam flow
Decreases fuel consumption
Decreases steam pressure
The ratio of the actual vacuum to the ideal vacuum in a condenser is called
Condenser efficiency
Vacuum efficiency
Nozzle efficiency
Boiler efficiency
The efficiency of a pressure-velocity compounded impulse turbine is __________ as compared to pressure compounded impulse turbine.
Same
Less
More
None of these
The numbers of fire tubes in a Cochran boiler are
75
115
165
225
The efficiency of the plant __________ with the mechanical draught.
Increases
Decreases
Remains constant
None of these
Gusset stays in a boiler are provided to
Prevent the bulging of flat surfaces
Avoid explosion in furnace
Prevent leakage of hot flue gases
Support furnace freely from top
While steam expands in turbines, theoretically the entropy
Remains constant
Increases
Decreases
Behaves unpredictably
Pick up the wrong statement about critical condition of steam
Latent heat is zero
Liquid directly becomes steam
Specific volume of steam and liquid is same
This is the maximum pressure limit
A vessel into which the steam is exhausted and condensed after doing work in an engine cylinder or turbine is known as
Steam condenser
Steam boiler
Steam preheater
Economiser
The cylinder dimensions of a compound engine may be designed on the basis of
Equal power developed in each cylinder for uniform turning moment
Equal initial piston loads on all pistons for obtaining same size of piston rod, connecting rod etc. for all cylinders
Equal temperature drop in each cylinder for economy of steam
All of the above
The proximate 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
With increase in load, convection superheater has
Drooping characteristic
Linear characteristic
Rising characteristic
Flat characteristic
A packaged boiler is one in which various parts like firing equipment, fans, feed pumps and automatic controls are
Supplied by same manufacturer loose and assembled at site
Supplied mounted on a single base
Purchased from several parties and packed together at site
Packaged boiler does not exist
In cross compounding, the cylinders are arranged
Side by side and each cylinder has common piston, connecting rod and crank
Side by side and each cylinder has separate piston, connecting rod and crank
At 90° and each cylinder has common piston, connecting rod and crank
At 90° and each cylinder has separate piston, connecting rod and crank
Cut-off ratio is the ratio of
Swept volume to the volume at cut-off
Volume at cut-off to the clearance volume
Volume at cut-off to the swept volume
Clearance volume to the volume at cut-off
An air preheater
Increases evaporative capacity of the boiler
Increases the efficiency of the boiler
Enables low grade fuel to be burnt
All of the above
The discharge is __________ at critical pressure.
Zero
Minimum
Maximum
None of these
The state of vapour under saturation condition is described by
Pressure alone
Temperature alone
Pressure and temperature
Pressure and dryness fraction
The size of a boiler drum in pulverised fuel fired boiler, as its size and capacity, (steam pressure and flow ratings) increase
Increases
Decreases
Remains unchanged
Increases/decreases depending on steam temperature requirements
The saturation temperature of steam with increase in pressure increases
Linearly
Rapidly first and then slowly
Slowly first and then rapidly
Inversely
The value of the reheat factor varies from
1.02 to 1.06
1.08 to 1.10
1.2 to 1.6
1.6 to 2
A throttle governed steam engine develops 15 kW with 280 kg per hour of steam and 35 kW with 520 kg per hour of steam. The steam consumption in kg per hour when developing 20 kW will be nearly
150 kg/h
210 kg/h
280 kg/h
340 kg/h
The pressure of feed water has to be raised before its entry into the boiler. The pressure is raised by a device known as
Feed pump
Injector
Feed check valve
Pressure gauge