Evaluation of Gas Turbine Performances and Nox and CO Emissions during the Steam Injection in the Upstream of Combustion Chamber

In this work, the gas turbine cycle is modified with the steam injection in the upstream of the combustion chamber. A steam generator of heat recovery, by using exhaust fumes, is installed in order to produce the suitable quantity of steam overheated to inject into the cycle. The interaction of the cycle various components and the properties thermodynamic variation of gas, due to the steam injection, as well as the gas turbine performances variations are taken into account. The steam flow injected to the air flow ratio and the compression ratio are varied on certain range exceed their practice of the acceptable limits slightly in order to study overall their effects on the characteristics of the cycle. A computer code was developed and all required data were taken from GE MS5002 gas turbine which is largely used in the industry of hydrocarbons. This work is followed by the steam injection influence on the NOx and CO emissions by using some existing correlations in the literature. The results obtained are in good agreement with the quantitative variation for the principal characteristics of the machine considered and qualitative for the NOx emissions in the atmosphere. The current technique of the modified cycle can be regarded as one of the possible means of the performances improvement of the gas turbines used in the field of hydrocarbons as well as a reduction in the NOx emissions.