Decreasing the condenser temperature while keeping the evaporator temperature constant will cause the refrigeration cycle COP to__________________?
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Answer: A. increase
Explanation
Decreasing the condenser temperature lowers the high-side pressure and work input, thereby increasing the COP of the refrigeration cycle. Lowering the condenser temperature reduces the compressor pressure ratio and decreases the required work input. A smaller work input for the same refrigeration effect results in a higher coefficient of performance. Refrigeration cycle efficiency depends directly on the temperature difference between evaporator and condenser coils. Condenser temperatures are determined by ambient cooling air or water temperatures supplied to heat exchangers. Thermodynamic cycle analysis shows that reducing high-side operating pressures improves overall system efficiency.
Maintaining clean condenser coils ensures low condensing temperatures and reduces electrical power consumption in chillers. HVAC operators optimize cooling tower water flow to keep condenser operating temperatures as low as possible. Energy conservation initiatives in refrigeration plants focus heavily on reducing high-side condensing pressures. Decreasing condenser temperature improves efficiency, making a decrease in COP incorrect. System performance changes predictably with thermodynamic property shifts, ruling out unpredictable outcomes. Remaining unaffected violates basic thermodynamic principles governing vapor compression cycle work requirements.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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