Hydroacoustical investigation on an generic underwater vehicle using Lighthill-Curle


Gungor E.

JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, cilt.34, sa.3, ss.1352-1364, 2019 (SCI-Expanded) identifier identifier

Özet

The flow noise generated by a generic underwater vehicle is modeled and solved in a numerical environment. By using the Large Eddy Simulation (LES), the hydrodynamic analysis is performed using the finite volume methods and the acoustic analogies modeling the sound propagation. Sound pressure levels, sound direction, noise spectra and acoustic trace are found in the fluid environment. In order to increase the accuracy, fine mesh structure was used and second order discretization was applied to the volume. By using the pressure-based commercial code, the flow dynamics equations are solved in filtering process and the pressure obtained from hydrodynamic solution is defined as an acoustic source. Along with this, in order to be able to verify the method, a numerical process was created which will be evaluated considering the experimental studies in the literature. The numerical results of the thrust and torque curves at different rpms and speeds for the 4382 propeller were compared with test data. In addition, the amplitude levels of the noise harmonics generated by the VP1304 propeller are obtained by hybrid method at the receivers in the numerical environment and the results are compared with the test data. With the verification of the current method, the noise characteristics of the underwater vehicle were found by the Lighthill-Curle method and the classification of noise sources was performed using hydrodynamic sources. Thus, the feasibility and application of current work, which is an important criterion in the design and development phases, has been demonstrated and developed in this paper.