Efficiency augmentation of gas turbine cycles

Abstract

Paper presented at the 8th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Mauritius, 11-13 July, 2011.The efficiency of gas turbine cycles can be enhanced by application of several methods. In the present contribution, the four most promising options e.g. compressor cooling, recuperation, reheating and elevation of turbine inlet temperature are discussed in detail. The potential of efficiency augmentation is depicted for all described methods with respect to the required effort. In addition, it is shown that the combination of different cycle improvement methods can give a disproportional high benefit because of upcoming synergy effects. For the compressor cooling it is worked out that an unconventional cooling by water injection gives a superior result over a conventional cooling. Furthermore, as any cooling of the compression process is accompanied with lower compressor outlet temperatures a strong potential for recuperation is provided by combining both methods. Finally, the obtainable efficiency of a gas turbine is determined for combination of several enhancement methods.