Vapour Compression Refrigeration Systems MCQs : This section focuses on the "Vapour Compression Refrigeration Systems" in Refrigeration and Air Conditioning. These Multiple Choice Questions (MCQs) should be practiced to improve the Refrigeration and Air Conditioning skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Vapour-compression refrigeration used in?
A. domestic refrigerators
B. commercial refrigerators
C. large-scale warehouses
D. All of the above
Explanation: Vapour-compression refrigeration used in domestic and commercial refrigerators, large-scale warehouses for chilled or frozen storage of foods and meats, refrigerated trucks and railroad cars, and a host of other commercial and industrial services.
Vapor-compression uses a circulating liquid refrigerant as the medium which absorbs and removes heat from the space to be cooled and subsequently rejects that heat elsewhere.
C. Can be true or false
D. Can not say
Explanation: True, Vapor-compression uses a circulating liquid refrigerant as the medium which absorbs and removes heat from the space to be cooled and subsequently rejects that heat elsewhere.
Circulating refrigerant enters the compressor in the thermodynamic state known as a?
B. saturated vapor
D. thermal expansion valve
Explanation: Circulating refrigerant enters the compressor in the thermodynamic state known as a saturated vapor.
The condensed liquid refrigerant, in the thermodynamic state known as a?
A. unisaturated liquid
B. unsaturated liquid
C. saturated liquid
D. None of the above
Explanation: The condensed liquid refrigerant, in the thermodynamic state known as a saturated liquid, is next routed through an expansion valve where it undergoes an abrupt reduction in pressure.
The vapor compression refrigeration system is similar to a ________
A. latent heat pump
B. latent heat engine
Explanation: The vapor compression refrigeration system is a latent heat pump, as it pumps its latent heat from the brine and delivers it to the cooler.
In which case does the compression process remains in superheated state?
A. Wet state
B. Dry state
C. Semi-dry state
Explanation: In case of dry state the compression process remains in superheated state i.e. for compression of dry-saturated vapor or superheated vapor.
Refrigerating effect corresponds to which of the following processes?
A. Condensing process
B. Expansion process
C. Vaporizing process
D. Compression process
Explanation: During evaporation, the refrigerant absorbs its latent heat of vaporization from the medium or system which is to be cooled. So, the heat absorbed by the refrigerant is known as Refrigerating effect carried out in the vaporizing process.
Which case is when the refrigerant compression process is carried while it’s wet?
A. Dry state
B. Semi-dry state
D. Wet state
Explanation: In case of wet state the vapor compression process remains in wet state i.e. for compression of refrigerant is carried out while it’s still wet and for dry state compression is done in dry state.
The COP of vapor compression refrigeration compared to simple air refrigeration system is ________
D. Can not say
Explanation: COP of vapor compression refrigeration compared to simple air refrigeration system is high due to the use of refrigerant and as it can be employed over large range of temperatures.
The superheated vapor then passes through the condenser.
C. Can be yes or no
D. Can not say
Explanation: Yes, The superheated vapor then passes through the condenser. This is where the circulating refrigerant rejects heat from the system as it cools and condenses completely. The rejected heat is carried away by either the water or the air.