Visualization of underwater radiated noise in the near- and far-field of a propeller-hull configuration using CFD simulation results

Underwater radiated noise is part of the anthropogenic emissions into the environment and as such a pressing problem for the preservation of the marine ecosystem. In order to direct attention to the most relevant noise sources associated with ships it is crucial to precisely determine the local origins of the acoustic emissions. As acoustics are by nature perceived through a very subjective auditory perception, visual post-processing support is required in engineering applications to assess the impact on structures and to create an understanding of the overall noise field geometrically, topologically, and directionally. In the context of CFD simulations, this may be achieved by considering the pressure pulses on domain boundary surfaces or passive surfaces, or by evaluating various volumetric information, such as Proudman acoustic sources or the Lighthill stress tensor, which is the fundamental input for many acoustic analogies including the Ffowcs-Williams-Hawkings method. For a propeller-hull configuration, the acoustic emissions from modeled and scale-resolved turbulence two-phase CFD analyses are evaluated in detail with different visualization methods. It is shown that the spatial distribution information of frequency domain pressure pulses, and the corresponding complex phase angles on specific passive geometries, as well as the Lighthill stress tensor may be utilized to create a better understanding of underwater acoustics. This allows the identification of source types and their respective excitation of the hull and emission characteristics of the hydrodynamic sources into the fluid domain, as well as the effect of the CFD simulation domain geometry extent.

Subjects

underwater radiated noise

propulsion

cavitation

visualization of sound sources

DDC Class

530: Physik

600: Technik

620: Ingenieurwissenschaften

Funding(s)

Effiziente Methoden zur Bestimmung der vom Propeller induzierten hydroakustischen Abstrahlung

Reduktion der hydroakustischen Emission von Propulsionssystemen; Kalkulation des durch Propulsionssystemen mit Rudern oder Flossenkappen emittierten Unterwasser-Schalls

Publication version

publishedVersion

Lizenz

https://creativecommons.org/licenses/by/4.0/

Name

jmse-11-00834-v3.pdf

Size

23.31 MB

Format

Adobe PDF

Options

Visualization of underwater radiated noise in the near- and far-field of a propeller-hull configuration using CFD simulation results