When a heat pump cycle operates between a condenser temperature of +27°C and an evaporator temperature of -23°C, its Carnot COP evaluates to_________________?
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Answer: D. 6
Explanation
Carnot COP for a heat pump is calculated by dividing condenser temperature by temperature difference. Converting temperatures to Kelvin gives 300 Kelvin for the condenser and 250 Kelvin for evaporator. Dividing 300 by the temperature difference of 50 yields a heat pump COP of 6. Heat pumps deliver useful heating to a space by consuming electrical work to move thermal energy. Thermodynamic calculations require absolute temperature values measured in Kelvin for accurate results. The temperature difference between the condenser and evaporator in this scenario equals 50 Kelvin.
Heating engineers evaluate heat pump performance to ensure efficient residential and commercial climate control. Higher source temperatures improve heating coefficients of performance in modern building heat pump installations. Understanding theoretical limits helps technicians optimize heating system designs for maximum energy savings. A COP of 0.2 miscalculates the temperature ratio and applies incorrect thermodynamic formula parameters. A COP of 1.2 fails to account for the actual thermal energy output delivered by heat pumps. A COP of 5 represents the refrigeration cycle calculation rather than the heat pump configuration.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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