Noise Reduction Using An Air-Permeable Ceiling

Abstract

A scaled (1 ft = 1 m) model of a German coffered ceiling and three variations were designed, built, and tested at Construction Engineering Research Laboratory in Champaign, II. To measure the efficiency of these ceilings, a scaled representation of the spectral range for small arms fire was radiated through the suspended models. The noise reduction measured for these models is compared to theoretical design curves calculated by Cremer in Beranek for attenuation in lined ducts. When the ceilings are considered to be arrays of short lined ducts, Cremer's theory predicts the experimental noise reduction. Attenuation is found to be linearly dependent on the depth of the ceiling. In order to attenuate lower frequencies, the spacing between baffles must be increased. Therefore, size constraints will determine a lower bound on frequencies effectively attenuated by such ceilings.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1992
Accession Number
ADA381749

Entities

People

  • Wayne H. Bradley

Organizations

  • University of Illinois Urbana–Champaign

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Absorption Coefficients
  • Acoustic Propagation
  • Angle Of Incidence
  • Attenuation
  • Far Field
  • Frequency
  • Illinois
  • Line Of Fire
  • Losses
  • Materials
  • Measurement
  • Noise
  • Noise Reduction
  • Porous Materials
  • Small Arms
  • Test Equipment
  • Transmission Loss

Readers

  • Acoustics.
  • Combustion and Flow Dynamics.
  • Energy Conservation and Renewable Energy Engineering.

Technology Areas

  • Space