Enhancing fluidic oscillator performance is pivotal for optimizing advanced active flow control systems. This study presents a novel optimization strategy utilizing the adjoint method to significantly increase outlet jet frequency and reduce internal pressure drops by refining feedback channel efficiency under operational mass flow rates. Employing a robust two-dimensional numerical framework based on the URANS equations coupled with the k-ω SST turbulence model, it is comprehensively investigated the impact of strategic modifications on oscillator performance. The approach involves precise adjustments to the Coanda surfaces, guided by sensitivity analysis and including the removal of their trailing edges (the point at which the fluid no longer adheres to the surface and starts to detach and move away). This critical modification facilitates the merging of vortices into a dominant vortex, substantially influencing jet flow dynamics by creating significant pressure differentials and disrupting flow symmetry. The asymmetrical evolution of these vortices activates a feedback mechanism that induces harmonic oscillations, thereby enhancing the outlet frequency through improved channel efficiency. Comprehensive analyses, including sensitivity like the Adjoint method, phase portrait evaluations and assessments of dynamic and frequency characteristics, confirm the effectiveness of these modifications. The optimized designs, particularly with a 12-degree alteration of the Coanda surface, demonstrate a remarkable increase in oscillation frequency exceeding 70%, along with notable reductions in pressure drop and enhancements in output momentum flux. These findings validate the proposed optimization strategy and underscore the potential of enhanced fluidic oscillators in applications requiring precise flow control, noise reduction, and improved heat transfer.

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