25. In a gas turbine plant, air is compressed through a pressure ratio of 6 : 1 from 15°C. It is then heated to the maximum permissible temperature of 750°C and expanded in two stages each of expansion ratio V6 , the air being reheated between the stages to 750°C. A heat exchanger allows the heating of the compressed gases through 75 per cent of the maximum range possible. Calculate : (i) The cycle efficiency (ii) The work ratio (iii) The work per kg of air. The isentropic efficiencies of the compressor and turbine are 0.8 and 0.85 respectively. (Ans. (i) 32.75% (ii) 0.3852 (iii) 152 kJ/kg)

25. In a gas turbine plant, air is compressed through a pressure ratio of 6 : 1 from 15°C. It is then heated to the maximum permissible temperature of 750°C and expanded in two stages each of expansion ratio V6 , the air being reheated between the stages to 750°C. A heat exchanger allows the heating of the compressed gases through 75 per cent of the maximum range possible. Calculate : (i) The cycle efficiency (ii) The work ratio (iii) The work per kg of air. The isentropic efficiencies of the compressor and turbine are 0.8 and 0.85 respectively. (Ans. (i) 32.75% (ii) 0.3852 (iii) 152 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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