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The utilization of electric fields for the control of technical combustion processes (EFCC, Electric Field Controlled Combustion) provides an interesting approach in present-day discussions regarding reductions in CO 2 emission levels and improved fuel efficiency. The technical feasibility of electric field control of turbulent premixed flames is demonstrated for the first time at technically relevant operating conditions. The technical criteria addressed include the efficiency of control at thermal powers above 50 kW, operating pressures in the order of 10 bar, air preheating, increased mixture exit velocities as well as swirl-stabilized flames. Capacitive coupling of electric fields is explored against the background of preferably non-intrusive integration into existing gas turbine systems. It is demonstrated that electric fields can be transmitted through ceramic burning chamber walls using capacitive coupling by electrodes deposited as coatings on the walls, thus avoiding sensitive mechanical parts as weak spots within the combustion chamber. No reasonable limitations are observed that might hinder a possible realization of flame control for technical combustion processes using EFCC. IntroductionThe influence of electric fields on flames is known for almost 200 years and was mentioned for the first time in 1814 [1]. In the 1960's and 1970's, several different studies attempted to characterize the observed effects and to utilize them for technical applications. The two main effects observed that are of technical importance are an increase in flame stability and a reduction of pollutant emissions. Therefore, the utilization of electric fields for the control of technical combustion processes (EFCC, Electric Field Controlled Combustion) provides an interesting approach in present-day discussions regarding reductions in CO 2 emission levels and improved fuel efficiency.Most of the previous studies in the area were limited to simple atmospheric laboratory flames with low thermal power and laminar or low-turbulence flow fields [2][3][4][5][6][7][8][9][10][11]. In order to extend the scope of research to technically relevant conditions, a new study was recently begun, dealing with the technical feasibility of flame control by electric fields in stationary gas turbine combustors. This study was conducted at the Institute for Engineering Thermodynamics (LTT) at the FriedrichAlexander-University of Erlangen-Nuremberg in close cooperation with the Siemens AG company within the framework of the research initiative "Power Plants for the 21 st Century" (KW21). It was shown that the application of electric fields for flame control can broaden the regime for stable operation as well as decrease overall pollutant emissions at relevant operating conditions, i.e., increased pressure, high exit velocity and air preheating as well as swirl stabilization. Moreover, in order to avoid the requirement for the installation of metallic electrodes inside the combustion chamber, the coupling of an electric field in a capacitive manner t...

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