Comparative evaluation of different combined cycle configurations having simple gas turbine, steam turbine and ammonia water turbine. (1st February 2019)

• Record Type: Journal Article
• Authors: Maheshwari, Mayank; Singh, Onkar
• Is Part Of: Energy. Volume 168(2019)
• Page Start: 1217
• Page End: 1236
• Publication Date: 2019-02-01
• Subjects: Gas turbine -- Heat recovery vapor generator -- Ammonia mass fraction -- Closed loop cooling; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2018.12.008
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: Gas/steam combined cycles have been increasingly used in power plants due to better energy utilization for getting better performance from them as compared to Brayton cycle based gas turbine plant or the Rankine cycle based steam turbine plant individually. However, there exists ample scope for further improvement in the performance of combined cycles through variations in their arrangements. The present study deals with the thermodynamic analysis of different combined cycle power plant configurations having the simple gas turbine with closed loop cooling of gas turbine blades and varying arrangements in the bottoming cycle. The variation in the bottoming cycle relies upon the effective utilization of energy available in the topping cycle. The bottoming cycle considered uses steam cycle or ammonia water cycle or its combination. The comparison of eight different combined cycle configurations considered in this study reveals that, the work output is maximum for simple gas turbine with bottoming cycle having reheat ammonia water turbine and steam turbine, with an output of 638 kJ/kg of air, first and second law efficiency of 54.95% and 57.87% respectively for ammonia mass fraction of 0.7. The exergy loss is found to be maximum for the combustion chamber followed by heat recovery vapor generator. Highlights: Comparison is made on the basis of work output, first law efficiency, second law efficiency. Comparison of the different configurations is performed on the basis of cooling load and ammonia-mass fraction. Mechanical chiller or ammonia-water mixture acts as coolant for cooling inlet air. Absorber and heat recovery vapor generator have maximum irreversibility in the combined cycle.