Coupled hydrodynamic ship wake and PE-based acoustic propagation model

• Published in: The Journal of the Acoustical Society of America 2003-04, Vol.113 (4), p.2187-2187
• Main Authors: Balani, A, Culver, R L, Bradley, D L, Paterson, E G, Di, X, Kunz, R F
• Format: Article
• Language: English
• Subjects: Brackish; Freshwater; Marine
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.4780114

A full-wave, one-way, 2D parabolic equation (PE) code is used to predict sound propagation through a complex hydrodynamic bubble field. The normalized velocity component obtained from a hydrodynamic ship wake model is the basis for constructing the bubble distribution. A three-dimensional field is used to represent the complex environment: down wake (toward or away from the ship), cross wake (perpendicular to the wake axis), and with depth. Although the hydrodynamic wake model generates three-dimensional wake-bubble fields, the PE program is a 2D model. The problem is assumed to be two-dimensional by taking various two-dimensional cuts of the wake field, which are then used in the PE simulation. The wake of a ship is a complicated and challenging environment in which to model acoustic propagation. Predictions are made for the representation of the wake at various distances from the source ship. From this study a few results are seen: (1) The sound level corresponding to the strength of a spherically spreading sound field can be obtained. (2) Sound propagation through the wake bubble field is a three-dimensional problem. (3) Small changes in void fraction can produce noticeable differences in the propagation.