Mini two-shaft gas turbine exergy analysis with a proposal to decrease exergy destruction

Document Type : Research Paper


1 Department of Mechanical Engineering, Khomeinishahr Branch, Islamic Azad University, Isfahan, Iran

2 Young Researchers and Elite club, Islamic Azad university Khomeini Shahr Branch, Isfahan, Iran


In this case study, exergy analysis is applied to a mini two-shaft gas turbine which is located in Islamic Azad University Khomeini Shahr Branch`s Thermodynamics laboratory and a proposal presented to make exergy destruction less using a Heat Recovery Water Heater (HRWH). Calculations were done for N2=20000 (rpm) constant and various N1 and after that for N1=60000 (rpm) constant and various N2. Results revealed that the highest exergy destruction rate occurs in combustion chamber in all conditions and a huge part of exergy destruction through the turbine exhaust. Increase in N1 leads to increases in all component exergy destruction rates. On the other hand, power turbine is the only component which is affected by changes in N2 and the exergy destruction rate increases with increase in N2. Moreover, exergy gained rate within HRWH increased with increase in N1 and is almost constant with changes in N2. In the same vein, exergetic efficiency of HRWH and exergy gained rate within HRWH are increased with decrease in water outlet temperature of HRWH.


[1] Moran M., Shapiro H., Fundamentals of Engineering Thermodynamics, 4th Edition, Wiley, New York (2000).
[2] Sarabchi K., Parametric Analysis of Steam Injected Gas Turbine Tycle, IGTI ASME COGEN-TURBO ASME(1992) 7: 209-214.
[3] Yaseen A. A. R., Exergy Analysis of a Single-Shaft Gas Turbine Power Plant with Steam Injection, Wasit Journal for Science and Medicine (2008) 2(1):116-132.
[4] Almasi A., Barzegra Avval H., Ahmadi P., Najafi A. F., Thermodynamic Modelling, Energy and Exergoeconomic Analysis and Optimiztion of Mahshar Gas Turbine Power Plant, Proceedings of the Global Conference Onglobal Warmin, Lisbon, Portugal (2011).
[5] Agarwal S., Mishra R. S,, Thermodynamic Analysis for Improvement in Thermal Performance of a Simple Gas Turbine Cycle Through Retrofitting Techniques (Inlet Air Evaporating Cooling, Steam Injection & Combined IAC and STIG), Proceeding of National Conference on Trend and Advances in Mechanical Engineering, YMCA University of Science and Technology, India (2012).
[6] Mousafarash A., Ameri M., Exergy and Exergo-Economic Based Analysis of a Gas Turbine Power Generation System, Journal of Power Technologies (2013) 93 (1):44-51.
[7] Azimian A. R,, Thermo-Economic Analysis of Power Cycles, Esteghlal (2005) 24 (1): 413-424.
[8] Ghazikhani M., Takdehghan H., Mousavi Shayegh A, Exergy Analysis of Gas Turbine Air-Bottoming Combined Cycle for Different Environment Air Temperature, Proceedings of 3rd International Energy, Exergy and Environment Symposium (2007).
[9] Sarabchi K., Parametric Analysis of Gas Turbine Cogeneration Plant from First and Second Law Viewpoint, IGTI, ASME COGEN-TURBO ASME (1992) 7:485-490.
[10] Bilgen E., Exergetic and Engineering Analyses of Gas Turbine Based Cogeneration Systems, Energy (2000) 25: 1215-1229.