In a turbine air expands from 5 bar, 520°C to 1 bar, 300°C. During expansion 10 kJ/kg of heat is lost to the surroundings which is at 0.98 bar, 20°C. Neglecting kinetic and potential energy changes, determine per kg of air : (i) The decrease in availability; (ii) The maximum work; (iii) The irreversibility. For air take : e, = 1.005 kJ/kg K ; h = e T, where c, is constant. (Ans. (i) 260.7 kJ/kg ; (ii) 260.7 kJ/kg ; (iii) 49.6 kJ/kg ]

In a turbine air expands from 5 bar, 520°C to 1 bar, 300°C. During expansion 10 kJ/kg of heat is lost to the surroundings which is at 0.98 bar, 20°C. Neglecting kinetic and potential energy changes, determine per kg of air : (i) The decrease in availability; (ii) The maximum work; (iii) The irreversibility. For air take : e, = 1.005 kJ/kg K ; h = e T, where c, is constant. (Ans. (i) 260.7 kJ/kg ; (ii) 260.7 kJ/kg ; (iii) 49.6 kJ/kg ]

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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