Abstract

Quantifying the coupling underlying synchronization in forced turbulent oscillator flows through phase-amplitude reduction analysis is typically computationally demanding. Here, the authors propose a data-driven approach coupling Stuart-Landau oscillator models with unknown forcing dynamics and apply it to the study of the wake behind a D-shaped body subject to periodic blowing. Periodically forced, oscillatory fluid flows have been the focus of intense research for decades due to their richness as a nonlinear dynamical system and their relevance to applications in transportation, aeronautics, and energy conversion. Here we derive a mechanistic model of the dynamics of forced turbulent oscillator flows by leveraging a comprehensive experimental study of the turbulent wake behind a D-shaped body under periodic forcing. We confirm the role of resonant triadic interactions in the forced flow by studying the dominant components in the power spectra across multiple excitation frequencies and amplitudes. We then develop an extended Stuart-Landau model that captures the system dynamics and synchronization regions. Further, it is possible to identify the model coefficients from sparse measurement data.