Analysis of the Effects of Water Injection on the Performance of a Gas Turbine

Abstract

The effect of water injection in the combustion chamber of an industrial gas turbine is studied by means of analytic relations. Equations for the estimation of changes in the main performance parameters are provided. The relations are derived on the basis of an order of magnitude analysis and taking into account variation of gas properties due to water injection as well as changes in the interrelation of component performance parameters. It is shown that water/fuel ratio is the main parameter on which performance deviations depend. Data from the performance testing of an industrial gas turbine are used to check the validity of the proposed relations. The comparison of the predictions to the test data shows that the mechanisms of performance deviations are well modeled by the analysis presented.