Water is pumped from a lower reservoir to a higher reservoir by a pump that provides 20 kW of shaft power. The free surface of the upper reservoir is 45 m higher than that of the lower reservoir. If the flow rate of water is measured to be 0.03 m3/s, determine a) The mechanical energy required to maintain the water flow, b) mechanical power that is converted to thermal energy during this process due to frictional effects. c) The mechanical efficiency of the pump. Answers: 0.03 m/s 20 kW Pump 45 m =0

Water is pumped from a lower reservoir to a higher reservoir by a pump that provides 20 kW of shaft power. The free surface of the upper reservoir is 45 m higher than that of the lower reservoir. If the flow rate of water is measured to be 0.03 m3/s, determine a) The mechanical energy required to maintain the water flow, b) mechanical power that is converted to thermal energy during this process due to frictional effects. c) The mechanical efficiency of the pump. Answers: 0.03 m/s 20 kW Pump 45 m =0

Sustainable Energy

2nd Edition

ISBN:9781337551663

Author:DUNLAP, Richard A.

Publisher:DUNLAP, Richard A.

Chapter18: Energy Storage

Section: Chapter Questions

Problem 20P

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