Component replacement TPA : a transmissibility-based structural modification method for in-situ transfer path analysis

Meggitt, JWR; Elliott, AS; Moorhouse, AT; Jalibert, A; Franks, G

Abstract

In-situ Transfer Path Analysis is a diagnostic method used to analyse the propagation of noise and vibration through
complex built-up structures. Its defining feature is the invariant characterisation of an assembly’s active components
(i.e. vibration sources) by their blocked forces. This invariant characterisation enables the downstream structural modification
of an assembly without affecting the sources’ operational characteristics. In practical engineering structures,
however, there is often a need to alter or replace components that reside within a vibration source, for example resilient
mounts. An upstream structural modification of this sort would alter the blocked force and thus invalidate any response
predictions made thereafter. Hence, an alternative approach is required. In the present paper a transmissibility-based
structural modification method is introduced. We derive a set of equations that relate the blocked force and forward
transfer functions obtained from an initial assembly, to those of an upstream modified assembly. Exact formulations
are provided, together with first and zeroth order approximations for resiliently coupled structures. These component
replacement expressions are verified by numerical examples.

• Journal Article Type: Article
• Acceptance Date: Jan 28, 2021
• Online Publication Date: Jan 30, 2021
• Publication Date: May 12, 2021
• Deposit Date: Jan 29, 2021
• Publicly Available Date: Feb 1, 2021
• Journal: Journal of Sound and Vibration
• Print ISSN: 0022-460X
• Publisher: Elsevier
• Volume: 499
• Pages: 115991
• DOI: https://doi.org/10.1016/j.jsv.2021.115991
• Publisher URL: https://doi.org/10.1016/j.jsv.2021.115991
• Related Public URLs: http://www.journals.elsevier.com/journal-of-sound-and-vibration/
• Additional Information: Funders : Engineering and Physical Sciences Research Council (EPSRC); Projects : EMBED; Grant Number: EP/P005489/1