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Vibroacoustic response of confined rotating flow: A physically-coupled numerical study
R Montillo1, A Carravetta1, O Fecarotta1
1Department of Civil, Architectural and Environmental Engineering, University of Naples "Federico II," Naples, Italy.
The Journal of the Acoustical Society of America
|March 19, 2026
Summary
This study introduces a coupled method to analyze noise from confined flows. It shows that including structural vibrations is crucial for accurate noise prediction in devices like turbomachines.
Area of Science:
- Acoustics
- Fluid Dynamics
- Computational Mechanics
Background:
- Confined flows within devices significantly impact flow characteristics and noise transmission.
- Accurate noise prediction in engineered systems requires understanding the interplay between fluid dynamics and structural response.
Purpose of the Study:
- To develop and validate a computational methodology for studying noise generated by confined flows.
- To investigate the influence of structural vibrations on noise radiated from enclosed fluid systems.
- To establish a framework for reliable noise prediction in devices such as turbomachines.
Main Methods:
- A coupled workflow linking computational fluid dynamics (CFD) and structural dynamic analysis was implemented.
- Pressure fields from CFD simulations served as forcing terms for structural vibration equations.
- The Ffowcs Williams-Hawkings acoustic analogy was used to compute noise radiated by the vibrating structure.
- An idealized turbomachine configuration was used to isolate fluid-dynamic-induced vibrations and structure-borne noise.
Main Results:
- Structural vibrations play a critical role in the noise generated by confined flows.
- Fluid-dynamic simulations alone can yield misleading noise predictions.
- The validated numerical framework accurately captures structure-borne noise contributions.
Conclusions:
- A coupled CFD-structure-acoustics approach is essential for accurate noise assessment in confined flow systems.
- Ignoring structural dynamics leads to underestimation or misrepresentation of radiated noise.
- The methodology provides a robust tool for designing quieter turbomachinery and similar devices.
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