An approximation to the frequency-average radiation efficiency of rectangular flat plates

• Published in: The Journal of the Acoustical Society of America 1999-10, Vol.106 (4_Supplement), p.2123-2123
• Main Authors: Bonilha, Murilo W., Fahy, Frank J.
• Format: Article
• Language: English
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.427988

The average radiation efficiency of plate modes which are resonant in a given frequency band is termed the frequency-average radiation efficiency and it is an extremely useful quantity in applications of Statistical Energy Analysis to interior or exterior noise control. In the present work, computation of the frequency-average radiation efficiency of flat plates is made on the basis of the vibration field correlation of randomly excited flat plate structures [M. W. Bonilha and F. J. Fahy, J. Sound Vib. 214, 443–467 (1998)]. The advantage of this representation is that the radiation efficiency can be economically computed for simply-supported, free, clamped, guided and spring-supported boundary conditions. In addition, corrections to account for the presence of stiffeners and plate curvature can also be incorporated in the computation. Furthermore, the current representation also allows the use of FEA-derived spatial correlation results for the case of plates with complex boundary conditions and accommodate spatially varying materials or geometric properties. Radiation efficiency results for various boundary conditions are presented. It is shown that results for simply-supported boundary conditions agree well with those obtained by Leppington et al. [F. G. Leppington, E. G. Broadbent, and K. H. Heron, Proc. R. Soc. London, Ser. A 382, 245–271 (1982)].