✦ LIBER ✦

THE MEASUREMENT OF SOUND POWER FLUX IN FLOW DUCTS

✍ Scribed by K.R. HOLLAND; P.O.A.L. DAVIES

Publisher: Elsevier Science
Year: 2000
Tongue: English
Weight: 469 KB
Volume: 230
Category: Article
ISSN: 0022-460X
DOI: 10.1006/jsvi.1999.2656

No coin nor oath required. For personal study only.

✦ Synopsis

This paper describes the development of robust procedures yielding reliable estimates of the nett sound power #ux associated with one-dimensional wave motion under strongly reactive conditions in #ow ducts. In such reverberant situations, the measurements must be su$ciently precise to clearly identify the small fraction of the total #uctuating wave energy that is being propagated through the system [1}4]. An expansion chamber, together with its inlet and outlet pipes radiating into a semi-anechoic space, was chosen as a simple but su$ciently representative example of such systems. Various practical problems, such as those arising from low signal-to-noise ratios, or any inadequacies of microphone calibration were investigated in detail, along with various strategies for minimizing their in#uence on the realism and reliability of the associated measurements. The most e!ective procedures were identi"ed by performing a sequence of comparisons between the resulting measurements and checking them against data generated with an existing and well-veri"ed prediction code.

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