A WAVENUMBER APPROACH TO MODELLING THE RESPONSE OF A RANDOMLY EXCITED PANEL, PART I: GENERAL THEORY

✍ Scribed by C. MAURY; P. GARDONIO; S.J. ELLIOTT

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 360 KB
• Volume: 252
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.2001.4028

✦ Synopsis

Part I of this paper presents a self-contained analytical framework for determining the vibro-acoustic response of a plate to a large class of random excitations. The wavenumber approach is used, which provides an insight into the physical properties of the panel response and enables us to evaluate e$ciently the validity of several simplifying assumptions. This formulation is used in Part II for predicting the statistical response of an aircraft panel excited by a turbulent boundary layer. In this paper, we "rst provide a general statement of the problem and describe how the spectral densities of the panel response can be obtained from an analysis of the system response to a harmonic deterministic excitation and a statistical model for the forcing "eld. The harmonic response of the system is then expanded as a series of the eigenmodes of the #uid-loaded panel and these #uid-loaded eigenmodes are approximated by a perturbation method. Then, we evaluate the conditions under which this series simpli"es into a classical modal formulation in terms of the in vacuo eigenmodes.

To illustrate the use of a wavenumber approach, we consider three examples, namely, the vibro-acoustic response of a panel excited by an incidence di!use acoustic "eld, by a fully developed turbulent #ow and by a pressure "eld which is spatially uncorrelated from one point to another. Convergence properties of the modal formulations are also examined.

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