Finite Element Subvolume Technique for Structural-Borne Interior Noise Prediction

Finite element structural and acoustic representations of a vibrating structure and enclosed acoustic volume are used in a study of structural-bo rne interior noise. The direct finite element nodal representations of the equations of motion result in a large system of unsymmetric equations. In this paper, an acoustic subvolume analysis technique is presented which reduces the degrees of freedom of the interior volume to modal form prior to the coupled system dynamic analysis. Analytical predictions are compared to results from an experimental program to verify the analysis procedures. From these comparisons, the acoustic subvolume technique is shown to be a reliable method to reduce the computational requirements for finite element acoustic analysis.

[1]  W. H. Mayes,et al.  Interior noise levels of two propeller driven light aircraft , 1975 .

[2]  A. Craggs,et al.  The use of simple three-dimensional acoustic finite elements for determining the natural modes and frequencies of complex shaped enclosures , 1972 .

[3]  J. F. Unruh.  Structure-Borne Noise Prediction for a Single-Engine General Aviation Aircraft , 1981 .

[4]  J. J. Catherines,et al.  Interior noise studies for general aviation types of aircraft, part I: Field studies† , 1978 .

[5]  O. Zienkiewicz.  The Finite Element Method In Engineering Science , 1971 .

[6]  Donald J. Nefske,et al.  Automobile Interior Noise Reduction Using Finite Element Methods , 1978 .

[7]  A. Craggs,et al.  A finite element method for damped acoustic systems: An application to evaluate the performance of reactive mufflers , 1976 .

[8]  A. Craggs.  The transient response of a coupled plate- acoustic system using plate and acoustic finite elements , 1971 .

[9]  James F. Unruh,et al.  Engine-induced structural-borne noise in a general aviation aircraft , 1979 .

[10]  W. Hurty.  Dynamic Analysis of Structural Systems Using Component Modes , 1965 .

[11]  J. J. Catherines,et al.  Interior noise studies for general aviation types of aircraft, part II: Laboratory studies† , 1978 .

[12]  Krishnamurty Karamcheti,et al.  Principles of ideal-fluid aerodynamics , 1966 .

[13]  K. Ishihara,et al.  The analysis of the acoustic field in irregularly shaped rooms by the finite element method , 1973 .

[14]  James A Cockburn,et al.  STRUCTURAL-ACOUSTIC RESPONSE, NOISE TRANSMISSION LOSSES AND INTERIOR NOISE LEVELS OF AN AIRCRAFT FUSELAGE EXCITED BY RANDOM PRESSURE FIELDS , 1968 .

[15]  J. Lea,et al.  A finite element method for determining the acoustic modes of irregular shaped cavities , 1976 .

[16]  I. M. Fyfe,et al.  A finite element analysis of the impedance properties of irregular shaped cavities with absorptive boundaries , 1978 .

[17]  Rimas Vaicaitis,et al.  Interior noise analysis and control for light aircraft , 1977 .

[18]  Y. Kagawa,et al.  Finite element simulation of an axisymmetric acoustic transmission system with a sound absorbing wall , 1977 .

[19]  A. Craggs,et al.  An acoustic finite element approach for studying boundary flexibility and sound transmission between irregular enclosures , 1973 .

[20]  M. F. Rubinstein,et al.  Dynamics of structures , 1964 .

[21]  R. Vaicaitis.  Noise transmission into a light aircraft , 1980 .