Papers Published

  1. Peretti, Linda F. and Dowell, Earl H., Experimental verification of the Asymptotic Modal Analysis method as applied to a rectangular acoustic cavity excited by structural vibration, American Society of Mechanical Engineers, Noise Control and Acoustics Division (Publication) NCA, vol. 9 (1990), pp. 1 - 7 .
    (last updated on 2007/04/10)

    Abstract:
    An experiment was performed on a rigid wall rectangular acoustic cavity driven by a flexible plate mounted in a quarter of one end wall and excited by white noise. The experiment was designed so that the assumptions of Asymptotic Modal Analysis (AMA) were satisfied for certain bandwidths and center frequencies. Measurements of sound pressure levels at points along the boundaries and incrementally into the interior were taken. These were compared with the theoretical results predicted with AMA, and found to be in good agreement, particularly for moderate (1/3 octave) bandwidths and sufficiently high center frequencies. Sound pressure level measurements were also taken well into the cavity interior at various points along the 5 totally rigid walls. The AMA theory, including boundary intensification effects, was shown to be accurate provided the assumption of large number of acoustic modes is satisfied, and variables such as power spectra of the wall acceleration, frequency, and damping are slowly varying in the frequency bandwidth.

    Keywords:
    Noise, Spurious Signal--White Noise;Vibrations--Analysis;Mathematical Models;Acoustics;Acoustic Variables Measurement--Intensity;