On the usage of acoustic radiation modes for Krylov subspace reduction of acoustic finite element models in the time domain

Abstract

Recent works have shown that Krylov subspace reduction of vibro-acoustic finite element models can lead to accurate reduced order models that are only a fraction of the size of the full system. However, one of the disadvantages of this reduction method is that the resulting reduced order model size is dependent on the number of uncorrelated inputs. This can be an issue for vibro-acoustic models in which the structural vibration is not explicitly modelled. For example, this could occur when the structural vibration is measured, such as with high speed cameras. In this case we might not know the structural properties, but we can measure full-field vibration patterns and apply them as acoustic boundary conditions. Thus, effectively implementing the boundary condition as a high number of uncorrelated inputs. It is known that at low frequencies a few acoustic radiation modes are responsible for most of the far-field sound radiation. Therefore, in this work we are investigating the creation of reduced order models through a decomposition of the input into radiation modes. It is shown how the input can be approximated by a few radiation modes and how to use these modes to create a reduced order model.

More information

Identifiers

ORCID for Sjoerd van Ophem: orcid.org/0000-0003-1050-7318

Catalogue record

Export record