Structural-acoustic finite element analysis of the automobile passenger compartment: A review of current practice

Abstract This paper contains a brief review of the formulation of the finite element method for structural-acoustic analysis of an enclosed cavity, and illustrations are given of the application of this analytical method at General Motors Corporation to investigate the acoustics of the automobile passenger compartment. Low frequency noise in the passenger compartment (in approximately the 20–200 Hz frequency range) is of primary interest, and particularly that noise which is generated by the structural vibration of the wall panels of the compartment. The topics which are covered in the paper include the computation of acoustic modes and resonant frequencies of the passenger compartment, the effect of flexible wall panels on the cavity acoustics, the methods of direct and modal coupling of the structural and acoustic vehicle systems, and forced vibration analysis illustrating the techniques for computing panel-excited noise and for identifying critical panels around the passenger compartment. The capabilities of the finite element method are illustrated by applications to the production automobile, and experimental verifications of the various techniques are presented to illustrate the accuracy of the method.

[1]  E. Dowell,et al.  THE EFFECT OF A CAVITY ON PANEL VIBRATION , 1963 .

[2]  R. H. Macneal,et al.  A New Method for Analyzing Fluid-Structure Interaction Using MSC-NASTRAN , 1979 .

[3]  S. K. Jha.  CHARACTERISTICS AND SOURCES OF NOISE AND VIBRATION AND THEIR CONTROL IN MOTOR CARS , 1976 .

[4]  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 .

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

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

[7]  E. Dowell,et al.  Acoustoelasticity - General theory, acoustic natural modes and forced response to sinusoidal excitation, including comparisons with experiment , 1977 .

[8]  D. J. Nefske,et al.  NASTRAN modeling and analysis of rigid and flexible walled acoustic cavities , 1975 .

[9]  G. Gladwell,et al.  On energy and complementary energy formulations of acoustic and structural vibration problems , 1966 .

[10]  J. Wolf.  Modal Synthesis for Combined Structural-Acoustic Systems , 1977 .

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

[12]  C. A. Joachim,et al.  Application of a Structural-Acoustic Diagnostic Technique to Reduce Boom Noise in a Passenger Vehicle , 1981 .

[13]  R. Lyon.  Noise reduction of rectangular enclosures with one flexible wall , 1963 .

[14]  S. H. Sung.  Automotive Applications of Three-Dimensional Acoustic Finite Elements , 1981 .

[15]  G. C. Everstine,et al.  The dynamic analysis of submerged structures , 1975 .

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

[17]  J. F. Unruh,et al.  Finite Element Subvolume Technique for Structural-Borne Interior Noise Prediction , 1980 .

[18]  Donald J. Nefske,et al.  Structural-Acoustic Finite Element Analysis of the Automobile Passenger Compartment , 1976 .

[19]  T. Priede.  Origins of automotive vehicle noise , 1971 .

[20]  S. K. Jha,et al.  A simplified finite element method for studying acoustic characteristics inside a car cavity , 1979 .

[21]  D L Smith.  EXPERIMENTAL TECHNIQUES FOR ACOUSTIC MODAL ANALYSIS OF CAVITIES , 1976 .

[22]  P. W. Eade,et al.  Acoustic Aspects of Railway Vehicle Design , 1976 .

[23]  J. T. Howlett,et al.  Prediction of light aircraft interior noise , 1976 .

[24]  G Jennquin,et al.  IS THE COMPUTATION OF NOISE LEVEL INSIDE A CAR FEASIBLE , 1972 .

[25]  Earl H. Dowell.  Master Plan for Prediction of Vehicle Interior Noise , 1980 .

[26]  Rimas Vaicaitis,et al.  Investigation of Interior Noise in a Twin-Engine Light Aircraft , 1978 .

[27]  A. J. Pretlove.  Free vibrations of a rectangular panel backed by a closed rectangular cavity by a closed rectangular cavity , 1965 .

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