A heat pump unit operates between two heat reservoirs with temperatures of 270 and 330 K. The heat pump itself has a temperature of 255 K during heat addition from the 270 K reservoir and a temperature of 350 K during heat rejection to the 330 K reservoir. The COP of the actual unit is 3.40, and the heat-transfer rate from the 270 K reservoir is 2000 kJ/min. Determine the entropy production rate, in kJ/min · K, for a. the heat pump unit itself b. the low-temperature heat-transfer process c. the high-temperature heat-transfer process d. Which process has the largest irreversibility? Now, for the same temperatures and a heat-transfer rate of 2000 kJ/min, reduce the actual COP to 3.10. Again, determine the entropy production rate for e. the refrigeration unit itself f. the low-temperature heat-transfer process g. the high-temperature heat-transfer process h. Which process now has the largest irreversibility?

A heat pump unit operates between two heat reservoirs with temperatures of 270 and 330 K. The heat pump itself has a temperature of 255 K during heat addition from the 270 K reservoir and a temperature of 350 K during heat rejection to the 330 K reservoir. The COP of the actual unit is 3.40, and the heat-transfer rate from the 270 K reservoir is 2000 kJ/min. Determine the entropy production rate, in kJ/min · K, for a. the heat pump unit itself b. the low-temperature heat-transfer process c. the high-temperature heat-transfer process d. Which process has the largest irreversibility? Now, for the same temperatures and a heat-transfer rate of 2000 kJ/min, reduce the actual COP to 3.10. Again, determine the entropy production rate for e. the refrigeration unit itself f. the low-temperature heat-transfer process g. the high-temperature heat-transfer process h. Which process now has the largest irreversibility?

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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