An investigation of ultralean stratified, disk stabilized, propane flames operated with acoustic modulation of the inlet velocity and\nfuel-air mixture profiles is presented. Transverse acoustic forcing was applied to the air, upstream of a double-cavity premixer\nsection, formed along three concentric disks, which fueled the stabilization region with a radial mixture gradient. Measurements\nand supporting Large Eddy Simulations with a nine-step mechanism for propane combustion were performed to evaluate variations\nin the ultralean flame characteristics under forced and unforced conditions.The effects of forcing on the heat release profiles and on\nthe interaction of the toroidal flame with the recirculation region are examined and discussed.The impact of the acoustic excitation\nof inlet conditions on the local extinction behavior is, also, assessed by monitoring a local stability criterion and by analyzing\nphase-resolved chemilumine scence images.
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