The suction pipe diameter of refrigerating unit compressor in comparison to delivery side is
Bigger
Smaller
Equal
Smaller/bigger depending on capacity
Correct Answer :
A. Bigger
Related Questions
Oil separator in a refrigeration cycle is installed
Before compressor
Between compressor and condenser
Between condenser and evaporator
Between condenser and expansion valve
Under cooling in a refrigeration cycle
Increases C.O.P
Decreases C.O.P
C.O.P remains unaltered
Other factors decide C.O.P
Superheating in a refrigeration cycle
Increases C.O.P
Decreases C.O.P
C.O.P remains unaltered
Other factors decide C.O.P
The evaporator changes the low pressure liquid refrigerant from the expansion valve into
High pressure liquid refrigerant
Low pressure liquid and vapour refrigerant
Low pressure vapour refrigerant
None of these
Reducing suction pressure in refrigeration cycle
Lowers evaporation temperature
Increases power required per ton of refrigeration
Lowers compressor capacity because vapour is lighter
All of the above
The coefficient of performance of a domestic refrigerator is ________ as compared to a domestic air-conditioner.
Same
Less
More
None of these
Which of the following statement is correct?
The constant enthalpy lines are also constant wet bulb temperature lines.
The wet bulb and dry bulb temperature are equal at saturation condition.
The wet bulb temperature is a measure of enthalpy of moist air.
All of the above
In order to cool and dehumidify a stream of moist air, it must be passed over the coil at a temperature
Which lies between the dry bulb and wet bulb temperatures of the incoming stream
Which lies between the wet bulb and dew point temperatures of the incoming stream
Which is lower than the dew point temperature of the incoming stream
Of adiabatic saturation of incoming stream
An evaporator is also known as
Freezing coil
Cooling coil
Chilling coil
All of these
In case of sensible heating of air, the coil efficiency is given by (where B.P.F. = Bypass factor)
B.P.F. - 1
1 - B. P.F.
1/ B.P.F.
1 + B.P.F.
The boiling point of carbon dioxide is
-20.5°C
-50°C
-63.3°C
-78.3°C
The minimum temperature to which water can be cooled in a cooling tower is
Dew point temperature of air
Wet bulb temperature of air
Dry bulb temperature of air
Ambient air temperature
An Electrolux refrigerator is called a __________ absorption system.
Single fluid
Two fluids
Three fluids
None of these
The advantage of dry compression is that
It permits higher speeds to be used
It permits complete evaporation in the evaporator
It results in high volumetric and mechanical efficiency
All of the above
In vapour compression cycle the condition off refrigerant is dry saturated vapour
After passing through the condenser
Before passing through the condenser
After passing through the expansion or throttle valve
Before entering the compressor
The sub-cooling in a refrigeration cycle
Does not alter C.O.P.
Increases C.O.P.
Decreases C.O.P.
None of these
In a saturated air-water vapour mixture, the
Dry bulb temperature is higher than wet bulb temperature
Dew point temperature is lower than wet bulb temperature
Dry bulb, wet bulb and dew point temperature are same
Dry bulb temperature is higher than dew point temperature
Air refrigerator works on
Reversed Carnot cycle
Bell Coleman cycle
Both (A) and (B)
None of these
The condensing pressure due to the presence of non-condensable gases, as compared to that actually required for condensing temperatures without non-condensable gases,
Will be higher
Will be lower
Will remain unaffected
May be higher or lower depending upon the nature of noncondensable gases
The human body feels comfortable when the heat stored in the body is
Positive
Negative
Zero
None of these
A mixture of dry air and water vapour, when the air has diffused the maximum amount of water vapour into it, is called
Dry air
Moist air
Saturated air
Specific humidity
During sensible cooling,
Relative humidity remains constant
Wet bulb temperature increases
Specific humidity increases
Partial pressure of vapour remains constant
In a spray washing system, if the temperature of water is higher than the dry bulb temperature of entering air, then the air is
Heated and dehumidified
Heated and humidified
Cooled and humidified
Cooled and dehumidified
The temperature of air recorded by a thermometer, when it is not affected by the moisture present in the air, is called
Wet bulb temperature
Dry bulb temperature
Dew point temperature
None of these
During humidification process, dry bulb temperature
Remains constant
Increases
Decreases
None of these
Choose the correct statement
A refrigerant should have low latent heat
If operating temperature of system is low, then refrigerant with low boiling point should be used
Pre-cooling and sub-cooling bf refrigerant are same
Superheat and sensible heat of a refrigerant are same
In aircraft, air refrigeration Cycle is used because of
Low weight per tonne of refrigeration
High heat transfer rate
Low temperature at high altitudes
Higher coefficient of performance
The refrigerant supplied to a compressor must be
Superheated vapour refrigerant
Dry saturated liquid refrigerant
A mixture of liquid and vapour refrigerant
None of these
In a vapour compression system, the condition of refrigerant before entering the expansion or throttle valve is
High pressure saturated liquid
Wet vapour
Very wet vapour
Dry vapour
Which of the following statement is wrong?
The performance of the vapour compression refrigerator varies considerably with both vaporising and condensing temperatures.
In vapour compression cycle, the useful part of the heat transfer is at the condenser.
In ammonia-hydrogen (Electrolux) refrigerator, no compressor, pump or fan is required.
The effect of under-cooling the liquid refrigerant is to decrease the coefficient of performance.