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When compared to vapour compression refrigeration, the gas cycle refrigeration system has the following feature:

When compared to vapour compression refrigeration, the gas cycle refrigeration system has the following feature: Correct Answer <span style="">Light weight and compact</span>

Explanation:

Comparison of the Gas cycle with vapour compression cycle:

  • The design and construction of the Gas cycle or Bell Coleman cycle or reversed Rankine cycle is simple and no complicated parts are used. This is why the Gas cycle is lightweight and compact.
  • Type of refrigerant used: In the vapour compression cycle liquids like Freon and ammonia is used as the refrigerant. In the gas cycle, the gas-like air is used as the refrigerant.
  • Heat exchangers: In the vapour compression refrigeration cycle condenser and evaporator are the two heat exchangers where the refrigerant gives up and absorbs heat respectively. The refrigerant undergoes a change in phase in both the heat exchangers. In the gas cycle, the refrigerant exchanges heat in the heat exchangers, but there is no phase change in the gas.
  • The efficiency of the cycle: The efficiency of the vapour compression cycle is more than that of the gas cycle. For producing the same amount of refrigerating effect in the gas cycle, a large volume of gas is required; hence the systems tend to become very large, bulky, and expensive, which are not affordable for domestic applications.
  • Cycle used: The vapour compression cycle works on the reverse Brayton cycle, while the gas compression cycle works on the reverse Rankine cycle.
  • Applications: The vapour compression cycle is most widely used for refrigeration purposes. It is used in household refrigerators, air-conditioners, water coolers, ice and ice cream makers, deep freezers, large industrial refrigeration and air-conditioning systems, etc. Since the size of the gas compression systems is very large, they are not used for domestic and industrial purposes. They are used widely in aircraft air-conditioning systems since in aircraft's air at very high pressures is available readily and there won’t be the need for air compressors. This makes the air-conditioning system in the aircraft lightweight and less power-consuming. The use of air as the refrigerant in aircraft prevents the dangers of fire from flammable refrigerants.

Important Points

  • The main difference between the vapour compression refrigeration cycle and the Bell Coleman gas refrigeration cycle is that in the gas cycle, an expander is used in place of a throttle valve because, in throttling of perfect gas, the temperature remains constant.

Related Questions

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