Closed space panel acoustic contribution degree identification method based on local measurement

Abstract

The invention discloses an enclosed space panel acoustic contribution degree identification method based on local measurement, and the method comprises the steps: setting two semi-enclosed holographicmeasurement surfaces in an enclosed space, and measuring the sound pressure values of the holographic measurement surfaces; based on an acoustic equivalent source principle, establishing an outer sound field virtual source surface and an inward sound field virtual source surface in the closed space, establishing a transfer relationship between the holographic measurement surface and the sound field virtual source surface, and calculating a source intensity column vector on the inward sound field virtual source surface; utilizing the admittance boundary condition of the surface of the to-be-measured vibration panel and the source intensity column vector on the inward sound field virtual source surface to calculate a scattering sound field generated when the inward sound field virtual source surface is incident to the surface of the to-be-measured vibration panel, and restoring the sound pressure and the normal vibration speed on the to-be-measured vibration panel under the free field condition; dividing the to-be-measured vibration panel into a plurality of discrete units, and calculating the acoustic contribution degree of the to-be-measured vibration panel to the closed sound field. According to the method, the local acoustic contribution degree of the closed space structure panel can be flexibly and quickly identified.

Description

technical field [0001] The invention relates to the technical field of noise source identification, in particular to a method for identifying the acoustic contribution of a panel in an enclosed space based on local measurement. Background technique [0002] The spatial sound field formed by the vibration of the complex elastic closed cavity structure under external excitation is the most representative type of sound field in engineering practice, such as the cabin sound field of automobiles, ships and airplanes. The comfort requirements are constantly improving, and people are paying more and more attention to the noise problem inside the closed space structure. After the external excitation energy is transmitted to the closed cavity structure, the panels vibrate and radiate structural noise into the acoustic cavity. The main factors that ultimately affect the sound field characteristics in the closed space are the vibration and acoustic characteristics of all the panels tha...

AI Technical Summary

Problems solved by technology

This method uses a set of holographic sound pressure measurements to reconstruct the entire sound field information, and uses the sound field equivalent principle to solve the acoustic contribution of each vibrating panel of the closed structure to any position in the cavity. Full-field acoustic measurements of the entire enclosed space, for larger sound source structures this requirement causes problems with increased measurement time and cost, reducing computational efficiency

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