### Resumé

shape from measurements in the field is often solved by combining a Boundary Element

Method with the Singular Value Decomposition and a regularization technique. In their standard

form these methods solve for the unknown normal velocities of the structure at the relatively

large number of nodes in the numerical model. Efficiently the regularization technique smoothes

the solution spatially, since a fast spatial variation is associated with high index singular values,

which is filtered out or damped in the regularization. Hence, the effective number of degrees of

freedom in the model is often much lower than the number of nodes in the model. The present

paper deals with an alternative formulation possible for the subset of radiation problems in

which a (structural) modal expansion is known for the structure. The inverse problem is

formulated in terms of modal amplitudes rather than of nodal velocities. The size of the inverse

problem and the built-in regularization can be controlled by choosing the number of modes

accounted for in the model.

Originalsprog | Engelsk |
---|---|

Titel | Proceedings of the 19th International Congress on Acoustics |

Redaktører | Antonio Calvo-Manzano, Antonio Pérez-López, Salvador Santiago |

Antal sider | 6 |

Forlag | Sociedad Española de Acústica |

Publikationsdato | 2007 |

ISBN (Elektronisk) | 84-87985-12-2 |

Status | Udgivet - 2007 |

Begivenhed | 19th International Congress on Acoustics - Madrid, Spanien Varighed: 2. sep. 2007 → 7. sep. 2007 Konferencens nummer: 19 |

### Konference

Konference | 19th International Congress on Acoustics |
---|---|

Nummer | 19 |

Land | Spanien |

By | Madrid |

Periode | 02/09/2007 → 07/09/2007 |

### Fingeraftryk

### Citer dette

*Proceedings of the 19th International Congress on Acoustics*Sociedad Española de Acústica.

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*Proceedings of the 19th International Congress on Acoustics.*Sociedad Española de Acústica, 19th International Congress on Acoustics, Madrid, Spanien, 02/09/2007.

**Inverse boundary element calculations based on structural modes.** / Juhl, Peter Møller.

Publikation: Bidrag til bog/antologi/rapport/konference-proceeding › Konferencebidrag i proceedings › Forskning › peer review

TY - GEN

T1 - Inverse boundary element calculations based on structural modes

AU - Juhl, Peter Møller

PY - 2007

Y1 - 2007

N2 - The inverse problem of calculating the flexural velocity of a radiating structure of a generalshape from measurements in the field is often solved by combining a Boundary ElementMethod with the Singular Value Decomposition and a regularization technique. In their standardform these methods solve for the unknown normal velocities of the structure at the relativelylarge number of nodes in the numerical model. Efficiently the regularization technique smoothesthe solution spatially, since a fast spatial variation is associated with high index singular values,which is filtered out or damped in the regularization. Hence, the effective number of degrees offreedom in the model is often much lower than the number of nodes in the model. The presentpaper deals with an alternative formulation possible for the subset of radiation problems inwhich a (structural) modal expansion is known for the structure. The inverse problem isformulated in terms of modal amplitudes rather than of nodal velocities. The size of the inverseproblem and the built-in regularization can be controlled by choosing the number of modesaccounted for in the model.

AB - The inverse problem of calculating the flexural velocity of a radiating structure of a generalshape from measurements in the field is often solved by combining a Boundary ElementMethod with the Singular Value Decomposition and a regularization technique. In their standardform these methods solve for the unknown normal velocities of the structure at the relativelylarge number of nodes in the numerical model. Efficiently the regularization technique smoothesthe solution spatially, since a fast spatial variation is associated with high index singular values,which is filtered out or damped in the regularization. Hence, the effective number of degrees offreedom in the model is often much lower than the number of nodes in the model. The presentpaper deals with an alternative formulation possible for the subset of radiation problems inwhich a (structural) modal expansion is known for the structure. The inverse problem isformulated in terms of modal amplitudes rather than of nodal velocities. The size of the inverseproblem and the built-in regularization can be controlled by choosing the number of modesaccounted for in the model.

KW - Boundary Element

KW - Inverse methods

KW - Acoustics

M3 - Article in proceedings

BT - Proceedings of the 19th International Congress on Acoustics

A2 - Calvo-Manzano, Antonio

A2 - Pérez-López, Antonio

A2 - Santiago, Salvador

PB - Sociedad Española de Acústica

ER -