How are the various efficiencies of a centrifugal pump related (where εm = mechanical, εv = volumetric, εma = manometric, εo = overall)?
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Answer: B. ηm = ηv . ηma
Explanation
Overall efficiency equals the mathematical product of volumetric efficiency and manometric efficiency. Mechanical losses inside bearings and packing are accounted for in pump efficiency relations. Volumetric efficiency addresses internal leakage losses within the centrifugal pump casing. Centrifugal pumps convert mechanical drive power into fluid power head. Pump efficiencies measure various mechanical, hydraulic, and volumetric loss mechanisms. Manometric efficiency relates theoretical head developed to actual head produced.
Pump manufacturers test commercial units to verify overall efficiency ratings for buyers. Plant operators monitor pump efficiencies to detect mechanical wear and schedule maintenance. Optimizing pump efficiency reduces electrical power consumption in large industrial facilities. Option A places efficiency terms in an incorrect mathematical arrangement. Option C incorrectly equates manometric efficiency to the product of mechanical and volumetric terms. Option D incorrectly defines volumetric efficiency as the product of mechanical and manometric terms.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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