This paper discusses the thermodynamics of power cycles where steam or water are mixed with air (or combustion gases) to improve the performance of stationary gas turbine cycles fired on clean fuels. In particular, we consider cycles based on modified versions of modern, high-performance, high-efficiency aeroderivative engines. The paper is divided into two parts. After a brief description of the calculation method, in Part A we review the implications of intercooling and analyze cycles with steam injection (STIG and ISTIG). In Part B we examine cycles with water injection (RWI and HAT). Due to lower coolant temperatures, intercooling enables us to reduce turbine cooling flows and/or to increase the turbine inlet temperature. Results show that this can provide significant power and efficiency improvements for both simple cycle and combined cycle systems based on aero-engines; systems based on heavy-duty machines also experience power output augmentation, but almost no efficiency improvement. Mainly due to the irreversibilities of steam/air mixing, intercooled steam injected cycles cannot achieve efficiencies beyond the 52–53 percent range even at turbine inlet temperatures of 1500°C. On the other hand, by accomplishing more reversible water–air mixing, the cycles analyzed in Part B can reach efficiencies comparable (RWI cycles) or even superior (HAT cycles) to those of conventional “unmixed” combined cycles.

Anon., 1993a, “Comprehensive Program Plan for Advanced Turbine Systems,” US Dept. of Energy, Office of Fossil Energy and Office of Energy Efficiency and Renewable Energy, Report to Congress, May.
Anon., 1993b, “1993 Performance Specs,” Gas Turbine World, Vol. 13.
Anon., 1993c, “The New GT-24 ABB 240 MW Gas Turbine,” ABB Company Publication, Baden, Switzerland.
Cheng, D. Y., 1978, “Regenerative Parallel Compound Dual-Fluid Heat Engine,” US Patent No. 4.128.994
Chiesa, P., Consonni, S., and Lozza, G., 1992, “Gas/Steam Cycles With Open-Circuit Steam Cooling of Gas Turbines Blades,” Proc. FLOWERS 92. Energy for the Transition Age, Firenze, Italy, pp. 303–323.
Chiesa, P., Consonni, S., Lozza, G., and Macchi, E., 1993, “Predicting the Ultimate Performance of Advanced Power Cycles Based on Very High Temperature Gas Turbine Engines,” ASME Paper No. 93-GT-223.
Cohn, A., Hay, G. A., and Hollenbacher, R. H., 1993a, “The Collaborative Advanced Gas Turbine Program—A Phase I Project Status Report,” Proc. 12th EPRI Gasification Conference, San Francisco, Oct. 27–29.
Cohn, A., Nakhamkin, M., Swensen, E., and Patel, M., 1993b, “Engineering Studies of the CASH and CASHING Cycles,” Proc. 12th EPRI Gasification Conference, San Francisco, Oct. 27–29.
Consonni, S., and Macchi, E., 1988, “Gas Turbine Cycles Performance Evaluation,” Proc. 2nd ASME Cogen-Turbo, Montreaux, Switzerland, pp. 67–77.
Consonni, S., et al., 1991, “Gas-Turbine-Based Advanced Cycles for Power Generation. Part A: Calculation Model,” Proc. 1991 Yokohama Int’l Gas Turbine Congress, pp. III-201–210.
Consonni, S., 1992, “Performance Prediction of Gas/Steam Cycles for Power Generation,” MAE Dept. Ph.D. Thesis No. 1893-T, Princeton University, Princeton, NJ.
Day, W. H., 1994, Turbo Power & Marine Systems (Connecticut, USA), personal communication.
Day, W. H., and Rao, A. D., 1992, “FT4000 HAT With Natural Gas Fuel,” Proc. 6th ASME Cogen-Turbo, Houston, TX, pp. 239–245.
Ghaly, O. F., McCone, A. I., and Nakhamkin, 1993, “Engineering and Economic Evaluation of the IGCASH Cycle,” Proc. 12th EPRI Gasification Conference, Houston, TX, pp. XX–00.
Horner, M., 1989, “LM8000 ISTIG Power Plant,” presentation given by the GE Marine and Industrial Engine Division, Cincinnati, OH.
Lozza, G., 1990, “Bottoming Steam Cycles for Combined Gas-Steam Power Plants: a Theoretical Estimation of Steam Turbine Performance and Cycle Analysis,” Proc. 4th ASME Cogen-Turbo, New Orleans, LA, pp. 83–92.
Lozza, G., 1993, “Steam Cycles for Large-Size High-Gas-Temperature Combined Cycles,” Proc. 7th ASME Cogen-Turbo Power, Bournemouth, UK, pp. 435–444.
Macchi, E., et al., 1991, “Gas-Turbine-Based Advanced Cycles for Power Generation. Part B: Performance Analysis of Selected Configurations,” Proc. 1991 Yokohama International Gas Turbine Congress, pp. III-211–219.
Oganowski, G., 1987, “LM5000 and LM2500 Steam Injection Gas Turbines,” Proc. 2nd Tokyo Int’l Gas Turbine Congress, pp. III–393–397.
Rice, I. G., 1993, “Steam Injected Gas Turbine Analysis: Part II—Steam Cycle Efficiency; Part III—Steam Regenerated Heat,” ASME Papers No. 93-GT-420, 93-GT-421.
I. G.
, “
Steam-Injected Gas Turbine Analysis: Steam Rates
, Vol.
, pp.
Stambler, I., 1993, “Next Generation ‘Superfans’ Could Plug Electric Utility Capacity Gaps,” Gas Turbine World, May-June, pp. 46–54.
Tittle, L. B., Van Laar, J. A., and Cohn, A., 1993, “Advanced Aeroderivative Gas Turbine: A Preliminary Study,” Proc. 12th EPRI Gasification Conference, San Francisco, Oct. 27–29.
Tomlinson, L. O., et al., 1993, “GE Combined Cycle Product Line and Performance,” General Electric rep. GER–3574D.
Werner, K. H., et al., 1993, “Deeside: an Advanced Combined Cycle Power Plant With ABB GT13E2 Gas Turbine for National Power PLC,” Proc. 7th ASME Cogen-Turbo Power, pp. 487–498.
This content is only available via PDF.
You do not currently have access to this content.