Development and Testing of a Low NOx Micromix Combustion Chamber for Industrial Gas Turbines

Abstract

The Micromix combustion principle, based on cross-flow mixing of air and hydrogen, promises low emission applications in future gas turbines. The Micromix combustion takes place in several hundreds of miniaturized diffusion-type micro-flames. The major advantage is the inherent safety against flashback and low NO x-emissions due to a very short residence time of reactants in the flame region. The paper gives insight into the Micromix design and scaling procedure for different energy densities and the interaction of scaling laws and key design drivers in gas turbine integration. Numerical studies, experimental testing, gas turbine integration and interface considerations are evaluated. The aerodynamic stabilization of the miniaturized flamelets and the resulting flow field, flame structure and NO x formation are analysed experimentally and numerically. The results show and confirm the successful adaption of the low NO x Micromix characteristics for a range of different nozzle sizes, energy densities and thermal power output. NOMENCLATURE Latin symbols A area AcUAS Aachen University of Applied Sciences AGP air guiding panel BR blockage ratio BRDR blockage ratio dimension ratio c velocity CFD computational fluid dynamics CO 2 carbon dioxide d inner diameter

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