3) The cold water system in a house is equipped with a pump. 12 kg of water at 5000kPa and 2°C will enter the pump until the pressure rises 3 times and the temperature is 12°C with 3kJ of heat loss. Hot water will be heated in a heat exchanger before entering the mixing chamber. The heat exchanger uses air at 150°C to heat 3kg of 5°C of 5MPA water until 120°C. The temperature of the air will be dropped 10 times than before. Later, the cold water will enter the mixing chamber to be mixed with hot water until the pressure of the water becomes 10MPA. Evaluate : a) work of the pump b) isentropic efficiency of the pump c) mass of the air used to heat the water d) heat add in the hot water e) temperature of the water at the exit of the mixing chamber in °C.

3) The cold water system in a house is equipped with a pump. 12 kg of water at 5000kPa and 2°C will enter the pump until the pressure rises 3 times and the temperature is 12°C with 3kJ of heat loss. Hot water will be heated in a heat exchanger before entering the mixing chamber. The heat exchanger uses air at 150°C to heat 3kg of 5°C of 5MPA water until 120°C. The temperature of the air will be dropped 10 times than before. Later, the cold water will enter the mixing chamber to be mixed with hot water until the pressure of the water becomes 10MPA. Evaluate : a) work of the pump b) isentropic efficiency of the pump c) mass of the air used to heat the water d) heat add in the hot water e) temperature of the water at the exit of the mixing chamber in °C.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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