Asymptotic modal analysis and statistical energy analysis

Dowell, Earl H.; Peretti, Linda F.

The sound field of a structural-acoustic enclosure was subject to experimental analysis and theoretical description in order to develop an efficient and accurate method for predicting sound pressure levels in enclosures such as aircraft fuselages. Asymptotic Modal Analysis (AMA) is the method under investigation. AMA is derived from classical modal analysis (CMA) by considering the asymptotic limit of the sound pressure level as the number of acoustic and/or structural modes approaches infinity. Using AMA, results identical to those of Statistical Energy Analysis (SEA) were obtained for the spatially-averaged sound pressure levels in the interior. AMA is systematically derived from CMA and therefore the degree of generality of the end result can be adjusted through the choice of appropriate simplifying assumptions. For example, AMA can be used to obtain local sound pressure levels at particular points inside the enclosure, or to include the effects of varying the size and/or location of the sound source. AMA theoretical results were compared with CMA theory and also with experiment for the case where the structural-acoustic enclosure is a rectangular cavity with part of one wall flexible and vibrating, while the rest of the cavity is rigid.

Document ID

19900017318

Acquisition Source

Legacy CDMS

Document Type

Conference Paper

Authors

Date Acquired

September 6, 2013

Publication Date

January 1, 1990

Subject Category

Report/Patent Number

Meeting Information

Meeting: Acoustical Society of America Meeting

Location: Saint Louis, MO

Country: United States

Start Date: November 27, 1989

End Date: December 1, 1989

Accession Number

90N26634

Funding Number(s)

Distribution Limits

Public

Work of the US Gov. Public Use Permitted.

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