Effects of the geometric modifications on the shear layer excitation source in co-axial side branches

Abstract

This comprehensive study delves into the interaction between shear layer oscillations and the acoustic field within co-axial cavities, spotlighting the efficacy of the sound source model as a reliable semi-empirical modeling methodology. The focus is on how the downstream acoustic boundary conditions, when varied, markedly alter the acoustic field and the aeroacoustic sound source within deep co-axial cavities. Furthermore, it highlights how different upstream distances influence the aeroacoustic resonance of a coaxial side branch and the resultant peak acoustic pressure and the sound source term. Interestingly, edge geometry modification, specifically edge rounding and chamfering, plays a crucial role in the phasing of the shear layer with the acoustic field, thereby affecting the excitation and resonance behavior of the aeroacoustic system. These alterations significantly impact the aeroacoustic response, including peak pressure and lock-in range. These findings, derived from rigorous experimentation and predictive modeling, provide valuable insights into aeroacoustic modeling within coaxial cavities, contributing significantly to the design of industrial applications seeking to avoid and mitigate aeroacoustic resonance.