Method for predicting sound insulation factors of rectangular solid flat plates

Abstract

The invention discloses a method for predicting sound insulation factors of rectangular solid flat plates. The method is characterized by comprising steps of building statistic energy analysis models for predicting the sound insulation of the flat plates and quantifying uncertain parameters by triangular fuzzy numbers; determining order and Gauss integration points of optimal square approximation functions, related to each parameter, of sound insulation models of the flat plates; sampling fuzzy parameters in subspaces spanned by the Gauss integration points in fuzzy carried sets; acquiring sound insulation optimal square approximation functions of the flat plates by the aid of flat plate sound insulation response in discrete formats at sample point locations; acquiring extreme points of the carried sets and further acquiring maximum and minimum points of the carried sets; determining maximum and minimum points of alpha cut sets on the basis of the extreme points of the carried sets, acquiring flat plate sound insulation interval limit of the alpha cut sets on the basis of the maximum and minimum points of the alpha cut sets and ultimately predicting the sound insulation factors of the rectangular solid flat plates. The method has the advantages that frequency response distribution of the sound insulation fuzziness of the flat plates can be accurately predicted by the aid of fuzzy number models which are used as input, and the computation efficiency and the computation precision can be obviously improved by the aid of optimal square approximation theories.

Description

technical field [0001] The invention relates to a method for predicting the sound insulation of a flat panel, in particular to a method for predicting the sound insulation of a rectangular solid flat panel. Background technique [0002] With the advancement of science and technology and the improvement of living standards, the noise problem has been paid more and more attention by people. Noise reduction engineering is one of the most important topics, no matter from the comfort of daily life or the safety of military and national defense. In the field of noise control, the use of solid flat panels for sound insulation is an important measure. In the process of sound wave propagation, the plate structure causes the change of the characteristic impedance of the sound field medium, so that the sound energy is reflected and absorbed by the plate structure, which further leads to the reduction of the sound energy through the plate structure to achieve sound insulation. Therefo...

AI Technical Summary

Problems solved by technology

However, in the process of statistical energy analysis, there are many uncertainties that have a significant impact on the prediction results. For example, the internal loss factor and coupling loss factor can only be measured by experiments or given by researchers’ engineering experience, while the internal loss factor of 10 % error will result in a 1 dB error in the response estimate and 100% error in the internal loss factor will result in a 3 dB error in the response estimate

At the same time, the coupling loss factor of flat panel sound insulation analysis is an order of magnitude smaller than its internal loss factor, which is given by experiment or experience and the order of calculation is 10 -2 ~10 -4 There is a large error in the internal loss factor or coupling loss factor within the range, and there are certain differences in the internal loss factor or coupling loss factor given by different researchers for the same connection state (screwed, welded, riveted or hinged, etc.) subsystems. subjectivity

In addition, statistical energy analysis parameters such as modal density and radiation ratio are functions of the geometric properties, material properties and acoustic field medium properties of the flat plate structure. The uncertainty of these structural properties induces the uncertainty of parameters such as modal density and radiation ratio. And further cause flat panel sound insulation fluctuations

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