UACE2017 Proceedings: Simulation of the Target Echo Strength with Hierarchical Matrices and the Boundary Element Method

Back


  • Session:
    Target Echo Strength-Measurements and Modelling
  • Paper:
    Simulation of the Target Echo Strength with Hierarchical Matrices and the Boundary Element Method
  • Author(s):
    Boris Dilba, Marian Markiewicz, Otto Von Estorff
  • Abstract:
    The acoustic scattering properties of underwater objects are of great interest since they characterize their detectable signature, which is also known as Target Echo Strength (TES). Depending on the angle of an impinged wave, the scattered response will propagate in all directions with different intensities and thus will result in a varying TES. The Boundary Element Method (BEM) is well suited for TES simulations due to the fact that the solution on domain O is determined once the Cauchy Data on the boundary G are known. Compared to the Finite Element Method (FEM) the standard BEM has the drawback of fully populated system matrices. Fast Boundary Element Methods like the Fast Multipole Method (FMM) or the Hierarchical Matrix (H-Matrix) approach reduce this drawback effectively. In contrast to the FMM, the H-Matrix procedure generates an approximation of the whole system matrix and provides a low rank arithmetic. The latter enables the generation of a LU-Factorization at costs of O(n log n) and provides a direct solution scheme in addition to the iterative GMRES-Method. Since an angular resolution of 0.1° for the monostatic TES leads to 1800 right-hand sides for symmetric objects, the application of the direct solver can be more advantageous than the iterative one. \nIn this contribution, different solution strategies for the mono- and bistatic TES calculation by means of the H-Matrix approach will be presented. The differences will be outlined by numerical experiments based on the Benchmark Target Strength Simulation (BeTSSi) submarine model provided by the Forschungsanstalt der Bundeswehr fur Wasserschall und Geophysik (FWG) in Kiel.
  •   Download the full paper

Contact details

  • Contact person:
    Mr Boris Dilba
  • e-mail:
  • Affiliation:
    Novicos GmbH
  • Country:
    Germany

Back