In this study, we experimentally investigate the synchronization of thermoacoustic modes in can-annular combustors using an electro-acoustic system. Synchronization occurs when multiple linearly unstable modes, with closely spaced frequencies and growth rates, interact nonlinearly, leading to a shift in their natural frequencies toward a common value. These synchronized oscillations result in complex mode shapes that cannot be predicted by traditional linear analysis due to the inherent nonlinearity of the phenomenon. To achieve synchronization experimentally, closely spaced acoustic modes of the system are identified and the natural symmetry of the combustor is intentionally broken. The experiments confirm that the synchronized oscillations can occur, and by combining theoretical considerations with experimental validation, this work provides insights on the nonlinear mode interactions in can-annular combustors.
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