Validation of Finite Element and Boundary Element Methods for Predicting Structural Vibration and Radiated Noise

Abstract

Analytical and experimental validation of methods to predict structural vibration and radiated noise is presented in this paper. A rectangular box excited by a mechanical shaker was used as a vibrating structure. Combined finite element method (FEM) and boundary element method (BEM) models of the apparatus were used to predict the noise radiated from the box. The FEM was used to predict the vibration, and the surface vibration was used as input to the BEM to predict the sound intensity and sound power. Vibration predicted by the FEM model was validated by experimental modal analysis. Noise predicted by the BEM was validated by sound intensity measurements. Three types of results are presented for the total radiated sound power: (1) sound power predicted by the BEM model using vibration data measured on the surface of the box, (2) sound power predicted by the FEM/BEM model, and (3) sound power measured by a sound intensity scan. The sound power predicted from the BEM model using measured vibration data yields an excellent prediction of radiated noise. The sound power predicted by the combined FEM/BEM model also gives a good prediction of radiated noise except for a shift of the natural frequencies that are due to limitations in the FEM model. Acoustic intensity, Noise, Vibration, Boundary clement, Finite element.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1992
Accession Number
ADA257376

Entities

People

  • A. F. Seybert
  • Fred B. Oswald
  • X. F. Wu

Organizations

  • National Aeronautics and Space Administration

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acoustic Measurement
  • Boundary Element Methods
  • Engineering
  • Experimental Data
  • Finite Element Analysis
  • Frequency Bands
  • Integral Equations
  • Intensity
  • Measurement
  • Measuring Instruments
  • Mechanical Engineering
  • Modal Analysis
  • Pressure Measurement
  • Radiation
  • Resonant Frequency
  • Sound Pressure
  • Three Dimensional

Fields of Study

  • Physics

Readers

  • Acoustics.
  • Computational Modeling and Simulation
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)