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14 Cards in this Set
- Front
- Back
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What is refrigeration |
Removing heat from a substance under controlled conditions or maintaining the temp of a body below the general temp of the surroundings. |
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What are the 4 fundamental changes of state or processes during refrigeration? |
Expansion Vaporisation Compression Condensation |
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What are the 4 parts/equipments needed for refrigeration |
Expansion device. Evaporator Compressor Condenser |
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Draw a diagram of the refrigeration set up. |
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Give the steps in a refrigeration process |
1. Refrigerant gas is compressed to a high pressure in compressor 2. After passing through the compressor it goes to the condenser 3. Hugh pressure gas is converted to thermal energy which is given off to the surroundings. The gas condenses to a liquid. 4. It passes to an expansion valve. 5. Pressure is lowered at the expansion valve. The boiling point temp is lowered too. 6. Lower temp absorbs heat from air passing over it in the evaporation. It is transformed form liquid to a gas again. 7. Process repeats. |
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What is a refrigerator |
A device taking heat from a cool body and delivering if to a hot body. |
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What is a refrigerant |
Heat carrying medium when absorbs from the cold medium to the hot medium.. |
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Types of refrigerants |
Nh3 C02 Air R11 |
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What are the 3 refrigeration systems |
Vapour compression Vapour absorption Air refrigeration |
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Which one is the most important system from a commercial point of view and practically |
Vapour compression RS |
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What should the working fluid in the vapour compression RS be like |
Easy to evaporate and condense quickly without leaving the plant. |
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What whole s during evaporation |
Abs heat from the air and turns from liquid to vapour |
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What happenes in the condenser |
Ejects heat to the hot body going from gas to liquid |
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Applications of refrigeration |
Air conditioning plants. Process refrigeration Freeze drying. |
