A vessel initially contains 5.0 kg of liquid water and 2.0 kg of ice at 0°C. Energy is added until the ice has just melted. The temperature at the boundary where heat transfer occurs is taken to be the system temperature during the process. The enthalpy of melting is 333.5 kJ/kg. Consider the following processes used to melt the ice. a. Heat is added from the environment at 20°C. Determine the entropy flux and the total entropy generation, both in kJ/K. b. Heat is added from a reservoir at 727°C. Determine the same quantities as in part (a). c. Paddle-wheel work is used to change the state. Determine the total entropy production for the process, in kJ/K. d. Comment on the relative degree of irreversibility for the three processes.

A vessel initially contains 5.0 kg of liquid water and 2.0 kg of ice at 0°C. Energy is added until the ice has just melted. The temperature at the boundary where heat transfer occurs is taken to be the system temperature during the process. The enthalpy of melting is 333.5 kJ/kg. Consider the following processes used to melt the ice. a. Heat is added from the environment at 20°C. Determine the entropy flux and the total entropy generation, both in kJ/K. b. Heat is added from a reservoir at 727°C. Determine the same quantities as in part (a). c. Paddle-wheel work is used to change the state. Determine the total entropy production for the process, in kJ/K. d. Comment on the relative degree of irreversibility for the three processes.

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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