This work presents a methodology to study the noise generated by confined flows, i.e., flows enclosed within a device, which therefore significantly influence both the flow characteristics and the transmission of noise. A coupling workflow is implemented to link computational fluid dynamics simulations and structural dynamic analysis, where the pressure field computed in the fluid domain provides the forcing terms for the structural vibration equations. Outside the solid structure, the Ffowcs Williams–Hawkings acoustic analogy is applied to compute the noise radiated by the vibrating structure. The numerical framework is implemented using a combination of open-source and in-house software. The underlying modeling assumptions are discussed and validated. The results highlight the critical role of structural vibrations and demonstrate that relying solely on fluid-dynamic simulations can lead to misleading noise predictions. To isolate fluid-dynamic-induced vibrations and the associated structure-borne noise, and to exclude contributions from the driving motor and mechanical components such as bearings, an idealized device is considered, representing a simplified turbomachine configuration.
Montillo et al. (Sun,) studied this question.