Acoustic qualities of ship wakes

The major influence on sound propagation and attenuation in surface ship wakes arises from the presence of bubbles. The aim of the research behind this paper is to obtain a better understanding of the propagation conditions for sound in surface ship wakes in order to be able to produce realistic sound propagation models for predicting acoustic qualities of wakes. A high resolution, multi-beam sonar, looking upward at a wake produced by a passing surface ship, has provided data characterizing the wake structure in the along-wake, the cross-wake and the depth directions. A simple wake model has been developed from historical data, and this model has been used with a 2D PE code to calculate the loss of acoustic energy in the wake. Understanding the complexity of the wake bubble structure, and its effect on acoustic propagation, remains a challenging research goal.