Refrigerant 134a enters an air-cooled condenser at 12 bars and 60°C, and leaves as a saturated liquid at 12 bars. Atmospheric air at 35°C is blown over the condenser tubes and leaves at 45°C. The heat transfer between the two fluid streams equals 25 MJ/h. Changes in kinetic and potential energy are negligible. Make any reasonable assumptions if necessary. Determine (a) the mass flow rates for the R-134a and the air, in kg/h, Hint: Use the energy conservation on each of the {uid streams separately. (b) the entropy production rate in the condenser, in kJ h-'K-, Hint: Use the entropy balance over the whole condenser.

Refrigerant 134a enters an air-cooled condenser at 12 bars and 60°C, and leaves as a saturated liquid at 12 bars. Atmospheric air at 35°C is blown over the condenser tubes and leaves at 45°C. The heat transfer between the two fluid streams equals 25 MJ/h. Changes in kinetic and potential energy are negligible. Make any reasonable assumptions if necessary. Determine (a) the mass flow rates for the R-134a and the air, in kg/h, Hint: Use the energy conservation on each of the {uid streams separately. (b) the entropy production rate in the condenser, in kJ h-'K-, Hint: Use the entropy balance over the whole condenser.

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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