The potential performance of optimized gas-steam combined cycles built around latest-generation gas turbine engines is analyzed, by means of energy/exergy balances. The options here considered are the reheat gas turbine and the H-series with closed-loop steam blade cooling. Simulations of performance were run using a well-tested Modular Code developed at the Department of Energy Engineering of Florence and subsequently improved to include the calculation of exergy destruction of all types (heat transfer, friction, mixing, and chemical irreversibilities). The blade cooling process is analyzed in detail as it is recognized to be of capital importance for performance optimization. The distributions of the relative exergy destruction for the two solutions—both capable of achieving energy/exergy efficiencies in the range of 60 percent—are compared and the potential for improvement is discussed. [S0742-4795(00)00902-9]

Issue Section:
Gas Turbines: Cycle Innovations
Keywords:
aerospace engines, turbines, gas turbines, filters, vibration control
Topics:
Blades, Combined cycles, Cooling, Cycles, Exergy, Gas turbines, Steam, Turbines, Exergy analysis, Pressure, Temperature, Heat recovery steam generators
1.
MPS (Modern Power Systems), 1998, “501 ATS Compressor Tests Show Progress,” staff reports, Gas Turbine Research at Whittle’s Test Site, Porvoo Proves 6FA Niche, pp. 41–55.
2.
Aoki, S., Uematsu, K., Suenaga, K., Mori, H., and Sugishita, H., 1998, “A Study of Hydrogen Combustion Turbines,” ASME Paper 98-GT-394.
3.
Carcasci, C., and Facchini, B., 1995, “A Numerical Method For Power Simulations,” presented at the GTI TURBO Expo Houston 1995.
4.
El Masri, M. A., 1997, “Exergy Balance Analysis of the Reheat Gas Turbine Combined Cycle,” presented at the 2nd ASME-JSME Thermal Engineering Conference, Honolulu, Hawaii.
5.
Kawaike, K., et al., 1984, “Effect of New Blade Cooling System with Minimized Gas Temperature Diluition on Gas Turbine Performance,” ASME Paper 84-GT-89.
6.
Koellen, O., and Koschel, W., 1986, “Effect of Film Cooling on the Aerodynamic Performance of a Turbine Cascade,” Heat Transfer and Cooling in Gas Turbine, AGARD Rep.
7.
Horlock, J. H., 1966, Axial Flow Turbines, Butterworths, London.
Copyright © 2000
 by ASME
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