• ion current
• ion chemistry
• cfd
• gas turbine
• sensors

The thesis objective is the understanding of models for formation and chemistry of ions in the methane combustion process.
This work is part of the project STech-005 (FARFAS 2014-2015), funded by Regione Toscana and leaded by General Electric-Baker Hughes (Nuovo Pignone) with the collaboration of University of Pisa (DICI, DESTEC), University of Florence (CeRTuS) and University of Siena.
The goal of the project is to advance the gas turbines technology for the production of electric energy, with the aim to achieve higher efficiency, flexibility and very low emissions.
One of the particular goals of the project is a study of the feasibility of the use of ion current sensors (constituted by electrodes) inside the gas turbine combustion chamber, with the final objective of a fast diagnostics of the combustion process.
Hence, the present thesis aims at the implementation of chemical kinetic mechanisms for the prediction of formation and evolution of ions in CFD codes; the developed tools will be then utilized by UniFi-CeRTuS for the modeling of a gas turbine.
The problem is extremely complex because it involves several phenomena: turbulence, methane oxidation including formation of many radicals (precursors of ionic species), formation and evolution of ions, interaction of ions with an electric field applied at the electrodes.
The general issue has been investigated with the identification of simpler benchmark cases (turbulent and laminar flames) used to validate the implementation and to comprehend specific phenomena and their interaction.