2019_programme: MODIFICATION OF THE ACOUSTIC RESPONSE OF A PARTIALLY BURIED HOLLOW CYLINDER AS A FUNCTION OF THE SEDIMENT CHARACTERISTICS AND OF THE LEVEL OF BURIAL



  • Session: 17. Modeling techniques for underwater acoustic scattering and propagation
    Organiser(s): Gunderson Aaron, Isakson Marcia
  • Lecture: MODIFICATION OF THE ACOUSTIC RESPONSE OF A PARTIALLY BURIED HOLLOW CYLINDER AS A FUNCTION OF THE SEDIMENT CHARACTERISTICS AND OF THE LEVEL OF BURIAL [invited]
    Paper ID: 820
    Author(s): Cristini Paul, Pailhas Yan, Hamon Ronan, Xenaki Angeliki, Urso Giorgio
    Presenter: Cristini Paul
    Presentation type: oral
    Abstract: Many buried objects can be found in the sediments of coastal waters all around the world. These objects, when they are chemical or explosive weapons can have a huge impact on human and animal life. It is therefore of great importance to be able to detect and classify them in order to secure a given area. However, the detection of such objects is a difficult task mainly because of the highly reverberating environment and the possible clutter. The discrimination between targets of interest and clutter contacts is difficult and the identification is distorted by the changes in the echo structure. Understanding how the signals issued from an object illuminated by an acoustic source are modified by its environment is therefore critical to improving the performances of detection and identification.\nIn this presentation, we will analyze by means of a numerical method the modifications of the time signal reflected by an object as a function of the sediment characteristics and of the level of burial. Since we need accurate numerical results, as close as possible to the real signals, we resort to a numerical method able to handle both the interface between the target and the sediment and the elastic properties of the object and of the sediment. The spectral finite element method which combines the accuracy of pseudo-spectral methods and the flexibility of finite elements is a method of choice for performing such numerical simulations. In a first step, we will validate the numerical simulations using a simple configuration where an analytical solution is available. Then, in a second step, several numerical simulations representing different configurations will be presented and analyzed. The influence of the structure of the object, the characteristics of the sediment and the level of the burial of the target will be evaluated.\n
  • Corresponding author: Dr Cristini Paul
    Affiliation: CNRS-LMA
    Country: France
    e-mail: