## Abstract

The scattering behaviour of a finite-sized elastodynamic scatterer in a homogeneous isotropic medium can be encapsulated in a scattering matrix (S-matrix) for each wave mode combination. Each S-matrix is a continuous complex function of 3 variables: incident wave angle, scattered wave angle and frequency. In the paper, the S-matrices for various scatterers (circular holes, straight smooth cracks, rough cracks and 4 circular holes in an area of interest) are investigated. It is shown that, for a given scatterer, the continuous data in the angular dimensions of an S-matrix can be represented to a prescribed level of accuracy by a finite number of complex Fourier coefficients. The finding is that the number of angular orders required to characterise a scatterer is a function of scatterer size and is related to the Nyquist theorem. The variation of scattering behaviour with frequency is examined next and is found to show periodic oscillation with a period which is a function of scatterer size and its geometry. The shortest period of these oscillations indicates the maximum frequency increment required to accurately describe the scattering behaviour in a specific frequency range. Finally, the maximum angular order and frequency increments for the chosen scatterers in a specific frequency range are suggested.

Original language | English |
---|---|

Title of host publication | 42nd annual review of progress in quantitative nondestructive evaluation |

Subtitle of host publication | Incorporating the 6th European-American workshop on reliability of NDE |

Publisher | American Institute of Physics (AIP) |

Number of pages | 9 |

ISBN (Print) | 9780735413535 |

DOIs | |

Publication status | Published - 10 Feb 2016 |

Event | 42nd Annual Review of Progress in Quantitative Nondestructive Evaluation (QNDE 2015): Incorporating the 6th European-American Workshop on Reliability of NDE - Minneapolis, Minnesota, United States Duration: 26 Jul 2015 → 31 Jul 2015 Conference number: 42 |

### Publication series

Name | AIP Conference Proceedings |
---|---|

Publisher | American Institute of Physics |

Volume | 1706 |

ISSN (Print) | 0094-243X |

ISSN (Electronic) | 1551-7616 |

### Conference

Conference | 42nd Annual Review of Progress in Quantitative Nondestructive Evaluation (QNDE 2015) |
---|---|

Abbreviated title | QNDE 2015 |

Country/Territory | United States |

City | Minneapolis, Minnesota |

Period | 26/07/15 → 31/07/15 |