On the impact of fuel injection angle in Euler–Lagrange large eddy simulations of swirling spray flames exhibiting thermoacoustic instabilities

This study deals with the fundamental problem of combustion dynamics in gas turbine combustors operating liquid fuel. In this framework present work proposes an academic fueled combustor sensitive to thermoacoustic instabilities, simulated via high-fidelity Large Eddy Simulations. The experimental setup addressed is SICCA-spray from EM2C laboratory featuring both stable and unstable flames depending on chamber length. proposed analysis, based Euler-Lagrange modeling approach, studies impact spray injection angle ? flame triggering longitudinal acoustic mode when using a longer quartz tube. For modeling, FIM-UR semi-empirical model adopted three different values: ?=35?, 45° 60°. conditions, proven have negligible anchoring point, however, mean length fuel distribution are found be slightly modified by velocity at which droplets enter chamber. thermoacoustically two well-established limit cycles same frequency similar amplitudes obtained injected ?=45? Contrarily, system stabilizes ?=35? pointing importance film layer formed inside injector for setup. Likewise, its appear critical as already suggested previous configuration. detailed analysis predictions then performed through investigation spatial fields local Rayleigh index following novel extension domain criterion complemented application Dynamic Mode Decomposition. It confirms that has significant effect response system. Indeed influence entering synchronization mechanism governing phase respect acoustics sustaining observed cycles. More specifically, couplings level evidenced introducing indices correlating fluctuations volume fraction evaporation rate pressure.