Article
Hybrid Aeroacoustic Simulation and Modal Decomposition of Turbulent Flow Over a Forward–Facing Step (en)
* Presenting author
Abstract:
In this work, we perform a Direct Numerical Simulation (DNS) of turbulent flow over a forward-facing step at Re = 16000 based on the step height using the spectral element method (SEM) as part of the Centre of Excellence Excellerat Phase 2. The spectral element method is well-established and widely used for delivering accurate high-fidelity flow field data due to its higher-order accuracy. However, there is limited literature on its suitability for computing acoustic source terms and conducting hybrid acoustic simulations. Thus, we aim to explore the potential of the SEM in providing reliable flow field data for accurate aeroacoustic source term computations and subsequent sound propagation simulations. Based on the DNS data, we conduct a hybrid aeroacoustic simulation and compare the results to the experiment. Moreover, we analyze the flow field data and the acoustic source terms in detail. Using streaming modal decomposition methods, we detect dominant sound generation mechanisms and reveal their connections to the fluctuating dynamics of the recirculation bubbles and their interactions with the turbulent boundary layer.