2019_programme: COMPARING TARGET ECHO STRENGTH MODELS FOR A GENERIC SUBMARINE

Back


  • Session: 21. Target Echo Strength-Measurements and Modelling
    Organiser(s): Williams Duncan, Nunn David, Nijhof Marten
  • Lecture: COMPARING TARGET ECHO STRENGTH MODELS FOR A GENERIC SUBMARINE [invited]
    Paper ID: 959
    Author(s): Curtis Alan, Nigro David, Harter Robert, Stirland Martin
    Presenter: Curtis Alan
    Presentation type: oral
    Abstract: Thales UK carries out work associated with the underwater acoustic signatures of a variety of platforms, with typical dimensions ranging from a few metres to hundreds of metres, and covering frequencies from a few Hz to hundreds of kHz. Supporting these projects is a comprehensive target echo strength capability, including in-water test facilities and modelling tools. This paper discusses some of the different types of model available to calculate the target echo strength of underwater objects.\nModelling tools are used for different purposes ranging from initial concept - stage design through to more detailed assessments of specific signature features and signature reduction measures. The models employed include analytic models based on simple, rigid geometric shapes; models for complex rigid bodies based on geometric optics methods; physical optics models for elastic bodies; and finite element analysis for arbitrary elastic bodies. The tools can be applied at differing levels of complexity and fidelity to detail, and may assume perfect reflection or utilise a full elastic solution. The use of these models is discussed, and the paper also describes a number of methods for representing the target echo strength predictions, including graphs of aspect - dependent integrated echo intensity; "hourglass" plots of echo intensity as a function of time of arrival and aspect; and frequency - azimuth plots.\nThe use of these modelling tools is demonstrated with the aid of particular examples, and results are presented for the predicted target echo strength of the BeTSSi generic submarine, which was the subject of an international collaborative workshop at The Hague in 2016. The paper discusses the differences between the predicted results from the various models, and considers the significance of these differences when selecting methods and applying the tools at different frequencies and for different purposes.
      Download the full paper
  • Corresponding author: Dr Curtis Alan
    Affiliation: Thales UK
    Country: United Kingdom
    e-mail:

Back