Numerical Modeling of Emissions and Thermoacoustics in Heavy-Duty Gas Turbine Combustion Systems

Lean premixed combustion systems have been established as state-of-the-art technology for heavy-duty gas turbines, allowing for low pollutant emissions. However, lean premixed combustion is also associated with thermoacoustic instabilities. Thus, modeling of the key performance parameters - pollutant emissions and thermoacoustics - has become mandatory in the design process. The present thesis contributes to the modeling of those key parameters. The objective was to describe and validate the methods for the prediction of emissions (NO_xand CO) and thermoacoustics. A low order approach for prediction of NO_xemissions and a high fidelity CFD-based approach for the combined prediction of emissions and thermoacoustics are presented within this work. The methods are selected and developed based on analysis of the current state of the art.