Structural-acoustic sensitivity analysis for optimization of shell geometry with respect to lower noise emission

An experimental and analytical study is made of the noise emission from the drawroll assembly of a textile draw-twisting machine. As an alternative to resorting to acoustic absorption techniques or the use of expensive high damping materials, investigations are made into the basic method of noise generation in the assembly. This leads to the incorporation of small design changes and the significantly lower noise emission thereby achieved is compared with the original emission. Aimed at the machine designer, the presentation is made in a straightforward, non-mathematical fashion.

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Development of acoustic sensitivity analysis based on experimental data and its applications.

Journal of the Japan Society for Precision Engineering ◽

10.2493/jjspe.56.98 ◽

1990 ◽

Vol 56 (1) ◽

pp. 98-102

Author(s):

Nobuyuki OKUBO ◽

Katsumi MASUDA

Keyword(s):

Experimental Data ◽

Sensitivity Analysis ◽

Acoustic Sensitivity

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Structural/Acoustic Sensitivity Analysis of a Panel With Manufacturing Variability

Design Engineering ◽

10.1115/imece2002-39227 ◽

2002 ◽

Author(s):

Sameer B. Mulani ◽

Michael J. Allen

Keyword(s):

Sensitivity Analysis ◽

Mean Value ◽

Design Parameters ◽

Sound Power ◽

Deterministic System ◽

Acoustic Response ◽

Element Analysis ◽

Advanced Mean Value ◽

Mean Value Method ◽

Acoustic Sensitivity

Sensitivity analysis is an essential component in the design of structural/acoustic systems. Current structural/acoustic sensitivity algorithms assume deterministic system design parameters and therefore predict changes in the deterministic response of the system. Due to variability associated with manufacturing tolerances most structural/acoustic systems consist of random and deterministic structural design parameters and therefore produce a probabilistic acoustic response. In this work, a structural/acoustic sensitivity algorithm is presented that considers systems comprised of random and deterministic design parameters. The new sensitivity algorithm calculates the change in the probabilistic vibro-acoustic response of a system due to a change in a deterministic design parameter. The new algorithm uses boundary element analysis, finite element analysis, and an advanced mean value method. An elastically supported panel subject to a non-uniform load is used to illustrate the algorithm. Variability is considered in the elastic support while structural sizing parameters are taken to be deterministic. The response of the panel is defined in terms of probabilistic radiated sound power. Probabilistic sound power sensitivity results are calculated and used to predict new sound power values via finite difference analysis. These results are compared successfully to results obtained through re-analysis.

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Reduction of Vehicle Interior Noise Using Our New Structural-Acoustic Sensitivity Analysis Methods

ASME 1991 Computers in Engineering Conference: Volume 2 — Finite Elements/Computational Geometry; Computers in Education; Robotics and Controls ◽

10.1115/cie1991-0118 ◽

1991 ◽

Author(s):

Ichiro Hagiwara ◽

Wakae Kozukue ◽

Zheng-Dong Ma

Keyword(s):

Sensitivity Analysis ◽

Coupled System ◽

Interior Noise ◽

Design Stage ◽

Vehicle Interior ◽

Acoustic Coupling ◽

Analysis Process ◽

Analysis Methods ◽

Orthogonality Conditions ◽

Acoustic Sensitivity

Abstract Since interior noise has a strong effect on vehicle salability, it is particularly important to be able to estimate noise levels accurately by means of simulation at the design stage. The use of sensitivity analysis makes it easy to determine how the analytical model should be modified or the structure optimized for the purpose of reducting vibration and noise of the structural-acoustic systems. The present work focused on a structural-acoustic coupling problem. As the coefficient matrices of a coupled structural-acoustic system are not symmetrical, the conventional orthogonality conditions obtained in structural dynamics generally do not hold true for the coupled system. To overcome this problem, the orthogonality and normalization conditions of a coupled system were derived by us. In this paper, our sensitivity analysis methods are applied to an interior noise problem of a cabin model. It will be shown how a sensitivity analysis process is performed, and how vibration and noise can be reduced.

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