Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781259822674
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
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Chapter 2.8, Problem 123RP
The pump of a water distribution system is powered by a 15-kW electric motor whose efficiency is 90 percent. The water flow rate through the pump is 50 L/s. The diameters of the inlet and outlet pipes are the same, and the elevation difference across the pump is negligible. If the pressures at the inlet and outlet of the pump are measured to be 100 kPa and 300 kPa (absolute), respectively, determine the
FIGURE P2–123
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The pump of a water distribution system is powered by a 15-kW electric motor whose efficiency is 95 percent. The water flow rate
through the pump is 50 L/s. The diameters of the inlet and outlet pipes are the same, and the elevation difference across the pump
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determine the mechanical efficiency of the pump.
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When water is pumped into a water tank 20 m above a lake with a flow rate of 70 l/s, 20.4kW of electrical power is consumed. Determine the efficiency of the pump-motor group by ignoring the friction losses in the pipes and the change in kinetic energy. Determine the pressure difference between the inlet and outlet of the pump.
Chapter 2 Solutions
Thermodynamics: An Engineering Approach
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