Session: 06-15-01 Unsteady Hydrodynamics, Vibrations, Acoustics and Propulsion

Paper Number: 81076

81076 - Numerical Analysis and Evaluation of the Sound Source in the Sea, Taking Into Account Changes in Sound Velocity, Emission Angles, Bed Roughness and the Presence of the Object 

Today, the issue of sound propagation underwater is important in many aspects. These include military applications, seabed mapping, environmental impacts, knowledge of marine organisms. One of the important issues in sound propagation due to the many complications underwater is its propagation path.

Various numerical methods have been proposed to study this issue, one of which is the theory of radiation

In this study, using this theory, the effects of sound speed change, propagation time and bed roughness and the presence of an object on the sound propagation path for different depths of sound sources have been investigated. For this purpose, a computer program with Python language has been developed. By examining the velocity profile of the mank, it was found that the sound rays move in certain areas without contacting the free surface and the floor, which is referred to as an acoustic channel.

Also, the results showed that, with the increase in the angle of diffusion, the exposure of the sound rays to the free surface and the substrate would increase, resulting in a higher energy loss of sound and a less distant sound. In the study of the effect of ripples on the sound propagation path, it was also found that, as the depth of the sound source increases, the sound area will decrease. But with the presence of an audio source in the center of the audio channel (the minimum sound speed), the collision of the rays with the rugged bed will be the lowest. Also, by placing an oval on the sound propagation path, it was found that if the beams hit the upper half of the body, it would be most likely to be detected and if the lower half of the object would collide, the lowest probability of detection would occur at the free surface. Ultimately, if the released audio angle falls below the submarine float and moves in the proper place to the sound channel, its detection probability at the surface will be minimized. Also, by accurately recognizing the sound velocity profiles and the rugged surfaces of the bed, it is possible to locate detectors in appropriate places by locating detectors in the sea.

Presenting Author: Roya Shademani IDRO

Authors:

Roya Shademani IDRO