How is the overall isothermal efficiency of an air compressor defined as a ratio_______________?
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Answer: A. isothermal h.p. to the BHP of motor
Explanation
Compressor efficiency compares theoretical thermodynamic work requirements against actual power consumption. Isothermal efficiency specifically uses theoretical isothermal horse power as the ideal energy benchmark. Dividing this ideal isothermal power by the actual brake horse power delivered yields the overall isothermal efficiency. Isothermal compression assumes constant temperature, representing the minimum theoretical work required for gas compression. Brake horse power measures the actual mechanical power delivered to the compressor shaft by its motor. Intercooling between stages helps practical compressors approach isothermal compression performance.
Industrial plant operators monitor compressor efficiency to minimize electrical power consumption costs. Comparing actual BHP to isothermal horsepower guides equipment selection for pneumatic systems. Compressor performance testing standards ensure equipment meets specified energy efficiency ratings. Option B compares isothermal horse power to adiabatic horse power rather than actual motor power input. Option C inverts the ratio, placing actual power in the numerator which yields values greater than one. Option D compares work values but lacks the specific motor brake horse power reference required here.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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