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
Correct Answer :
B. Barometric pressure - actual pressure
Related Questions
During polytropic process
Heat transfer takes place across cylinder walls
Work is done
Steam may be wet, dry or superheated after expansion
All of the above
In a throttling process
Heat transfer takes place
Work is done by the expanding steam
Internal energy of steam changes
None of the above
Lancashire boiler is
Stationary fire tube boiler
Internally fired boiler
Horizontal boiler
All of these
A safety valve in a locomotive starts leaking. The leaking medium will be
Water
Dry steam
Wet steam
Super heated steam
When steam after doing work in the cylinder passes into a condenser, the engine is said to be a
Slow speed engine
Vertical steam engine
Condensing steam engine
Non-condensing steam engine
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
Receiver type compound engine
Tandem type compound engine
Woolf type compound engine
Both (A) and (B)
Hard coke is used in
Cement industry
Thermal power plant
Blast furnace
Domestic use
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
Sulphur content of fuels is very important to the plant operators because it
Has high heating value
Retards electric precipitation
Promotes complete combustion
Has highly corrosive effect
The critical pressure at which latent heat of vaporisation is zero is
225.65 kgf/ cm²
273 kgf/ cm²
100 kgf/ cm²
1 kgf/ cm²
The heat loss in a boiler takes place in the form of
Heat carried away by flue gases
Heat carried away by ash
Moisture present in fuel and steam formed by combustion of hydrogen in fuel
All of the above
The number of flue tubes in Lancashire boiler is
Zero
One
Two
Four
A device used to heat feed water by utilising the heat in me exhaust flue gases before leaving through the chimney, is known as
Economiser
Fusible plug
Superheater
Stop valve
Steam exhaust from high pressure turbine is reheated in
Boiler drums
Superheater tubes
Economiser
A separate coil located in convection path.
The diameter of internal flue tubes in a Lancashire boiler compared to its shell is
One-half
One-third
Two-fourth
Two-fifth
An economiser in a boiler
Increases steam pressure
Increases steam flow
Decreases fuel consumption
Decreases steam pressure
An air preheater is installed
Before the economiser
Before the superheater
Between the economiser and chimney
None of these
The velocity of steam at throat of the nozzle is __________ the velocity of sound.
Equal to
Less than
More than
None of these
Pulverised fuel is used for
Better burning
More calorific value
Less radiation loss
Medium sized units
An economiser is generally placed between
Last superheater or reheater and air preheater
Induced draft fan and forced draft fan
Air preheater and chimney
None of the above
Water tube boilers are
Internally fired
Externally fired
Internally as well as externally fired
None of these
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
The rate of steam produced in Benson boiler is
100 tonnes/h
135 tonnes/h
175 tonnes/h
250 tonnes/h
The pressure of steam __________ while flowing through a nozzle.
Increases
Decreases
Remains constant
None of these
The main object of a boiler trial is
To determine the generating capacity of the boiler
To determine the thermal efficiency of the boiler when working at a definite pressure
To prepare heat balance sheet for the boiler
All of the above
Stoichiometric quantity of air is the
Air present in atmosphere at NTP conditions
Air required for complete combustion of fuel with no excess air
Air required for optimum combustion so as to have reasonable excess air
Air required to convert CO into CO₂
A boiler in India should conform to safety regulations of
DIN
BS
ASTM
IBR
1 kg.m is equal to
9.81 Joules
102 Joules
427 Joules
None of these
A binary vapour plant consists of
Steam turbine
Steam condenser
Mercury boiler
All of these
The function of an eccentric rod is
To provide reciprocating motion to the slide valve
To convert reciprocating motion of the piston into rotary motion of the crank
To convert rotary motion of the crankshaft into to and fro motion of the valve rod
To provide simple harmonic motion to the D-slide valve