Journal of South China University of Technology(Natural Science Edition) ›› 2024, Vol. 52 ›› Issue (11): 1-8.doi: 10.12141/j.issn.1000-565X.240029

• Architecture & Civil Engineering •     Next Articles

Influence of Near-Field Acoustic Holography Reconstruction Parameters on the Accuracy of Sound Insulation Measurement

WANG Hongwei1,2(), ZHANG Guangyao1, SHEN Tao3(), LI Shujie1, YANG Chenxi1, ZHANG Yang1   

  1. 1.School of Architecture,South China University of Technology,Guangzhou 510640,Guangdong,China
    2.State Key Laboratory of Subtropical Building and Urban Science,South China University of Technology,Guangzhou 510640,Guangdong,China
    3.Infrastructure Department,South China University of Technology,Guangzhou 510640,Guangdong,China
  • Received:2024-01-16 Online:2024-11-25 Published:2024-06-07
  • Contact: 沈涛(1982—),男,工程师,主要从事文物建筑修缮研究。 E-mail:tshen@scut.edu.cn
  • About author:王红卫(1975—),男,教授,博士生导师,主要从事建筑声学和环境声学研究。E-mail:wanghw@scut.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(52078218)

Abstract:

Equivalent source method near-field acoustic holography can be applied in sound insulation measurement of the building components. When near-field acoustic holography is used to measure the sound insulation volume of components, the reconstruction parameters significantly affect the acoustic field reconstruction results. Based on the theoretical analysis of near-field holographic acoustic insulation measurement by equivalent source method, the compound sound pressure signal of the surface of the component was measured by the microphone array, and the sound insulation volume and surface normal sound intensity distribution of the component were obtained through the acoustic field reconstruction. To further investigate the influence of reconstruction parameters on the accuracy of equivalent source method near-field acoustic holography, experiments on sound insulation measurement of building components were carried out in the sound insulation room by the control variable method in comparison with the traditional sound pressure method. The results show that when the position of the equivalent source surface changes from -2 cm to -5 cm, the average error value of the reconstruction of the surface normal sound intensity increases from 3.9 dB to 5.6 dB, and the average error value of the reconstruction of the sound insulation volume increases from 5.2 dB to 6.9 dB, and the measurement error increases with the distance of the equivalent source surface, so it is suitable for the equivalent surface to be close to the sound source surface. When the holographic measurement surface distance is 4, 8, and 16 cm, the average error values of the reconstruction of the surface normal sound intensity are 0.6, 1.9, and 5.5 dB, and the average error values of the reconstruction of the sound insulation volume are 0.9, 1.4, and 4.6 dB, respectively. The measurement errors increase with the holographic measurement surface distance, so it is recommended to keep the holographic measurement surface distance within 8 cm. When the number of equivalent source points is consistent with the number of measuring points on the holographic surface, the difference with the traditional sound pressure method is only 0.84 dB. When the number of equivalent source points is inconsistent with the number of measuring points on the holographic surface, the average error values of the reconstruction of the sound insulation volume and surface normal sound intensity distribution increase to 4.6~6.8 dB. By optimizing the reconstruction parameters, the accuracy of component sound insulation measurement can be effectively improved. It has important reference significance for laboratory measurement of sound insulation performance and methods of building components and has high reference value in the practical application of sound insulation measurement technology.

Key words: acoustic holography, acoustic field measurement, sound insulation measurement, reconstruction parameter, equivalent source method

CLC Number: