Practical deveropping study on low frequency sound absorption by preforated plate sturucture

2015 Fiscal Year Final Research Report

• Project/Area Number: 25420606
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Architectural environment/Equipment
• Research Institution: Niigata University
• Principal Investigator: IWASE Teruo 新潟大学, 自然科学系, 名誉教授 (30114391)
• Co-Investigator(Kenkyū-buntansha): SUGIE Satoshi 一般財団法人, 建築音響研究室, 研究員 (00280644)
• Co-Investigator(Renkei-kenkyūsha): NIshimura Shinya 新潟大学, 自然科学系, 教授 (50180641)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ヘルムホルツ共鳴器 / 低周波騒音 / 音響管法 / 音響インピーダンス / 吸音率 / ペアガラス / 低音域共鳴透過

Outline of Final Research Achievements

Study on Helmholtz resonator with extension tube material behind opening hole to realize high sound absorption at low frequency was executed. In this research, measurements of acoustic impedance and the sound absorption coefficient for a lot of various test samples by use of sound tube method were executed.
Relation and dependence of the acoustic impedance on shape sizes and frequency were arranged. As the results, computing model to predict the resonant frequency, the acoustic impedance, and the sound absorption coefficient could be established, and for example, high sound absorption coefficient of 100% at low frequency 50 Hz by very small size with thickness of 1/40 of wavelength was proposed. stance based on this model. It means miniaturization of the resonator can be realized, and recovering way for efficiency of sound insulation lost in double leaf glass window by inserting of the small resonator was proposed. Effectiveness of our proposal was confirmed by experiments.

Free Research Field

建築音響、騒音制御