If the condenser temperature remains unchanged, how does the C.O.P of a refrigeration cycle respond to a rise in evaporator temperature______________________?
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Answer: A. increase
Explanation
Raising the evaporator temperature increases suction pressure and refrigerant vapor density. Higher suction density increases mass flow rate and improves refrigeration COP. Reducing the temperature lift between evaporator and condenser enhances cycle efficiency. Coefficient of performance measures cooling output divided by compressor work input. Compressor volumetric efficiency improves when suction pressure increases. Thermodynamic cycles operate more efficiently with smaller evaporator-condenser temperature gaps.
HVAC system designers keep evaporator temperatures as high as comfort cooling allows. Chilled water setpoint adjustments significantly impact overall commercial building energy consumption. Optimizing evaporator operating conditions reduces electricity costs for industrial refrigeration. Decrease is incorrect because higher suction pressure improves thermodynamic performance. Remain unaffected is false since compressor work and cooling capacity change directly. Unpredictable behavior does not occur because thermodynamic laws govern cycle efficiency.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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