Vapor absorption refrigeration systems normally employ which working fluid combination___________________?
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Answer: E. ammonia
Explanation
Vapor absorption refrigeration systems commonly use an ammonia-water working fluid combination where ammonia acts as the refrigerant. Ammonia possesses exceptional thermodynamic properties that make it highly effective for continuous absorption cooling cycles. In this system, water serves as the absorbent liquid while ammonia vapor provides the primary refrigeration effect. Vapor absorption systems substitute thermal energy input for the mechanical compressor used in standard compression cycles. Ammonia has a very high latent heat of vaporization, enabling efficient heat absorption in industrial cooling loads. The affinity between ammonia and water allows the absorber to dissolve refrigerant vapor effectively under low pressure.
Freon-11 is a chlorofluorocarbon typically used in large centrifugal vapor compression chillers rather than absorption units. Freon-22 is commonly deployed in standard vapor compression air conditioning systems rather than ammonia-water setups. Carbon dioxide operates primarily in high-pressure transcritical vapor compression cycles instead of absorption systems.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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