Estimation of sound absorption coefficient at modal frequencies using decay time measurements and eigenvalue model in a small room

Čurović, Luka (author), Murovec, Jure (author), Železnik, Anže (author), Prezelj, Jurij (author)

Measuring the sound absorption coefficient in a small reverberation room below the Schroeder frequency is a challenging task and the results are subject to a high degree of uncertainty. Recent research shows that the low-frequency acoustic properties of the enclosure and the test sample should be characterized by quantities that describe the modal sound field. The aim of this paper is to present a method for estimating the absorption coefficient of a test sample at modal frequencies in the low frequency range and to demonstrate its applicability in a small room. The hybrid inverse approach is based on eigenvalue measurement data coupled with a finite element model to estimate the sound-absorbing properties of a small room and the test sample. The method was tested experimentally and the results were consistent with those of the long impedance tube method. The applicability of the proposed method was further demonstrated by the in-situ characterization of different acoustic samples in the low frequency range.

• Language: English
• Keywords: small room, sound absorption, low frequency, time-frequency method, finite element method, decay time, material characterization
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: Str. 1530-1544
• Numbering: Vol. 43, iss. 3
• PID: 20.500.12556/RUL-166794
• UDC: 534:519.62
• ISSN on article: 2048-4046
• DOI: 10.1177/14613484241258622
• COBISS.SI-ID: 197944323
• Publication date in RUL: 24.01.2025

Record is a part of a journal

• Title: Journal of low frequency noise, vibration, and active control
• Shortened title: J. low freq. noise vib. act. control
• Publisher: Sage Publications
• ISSN: 2048-4046
• COBISS.SI-ID: 526419993

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: majhna odmevnica, absorpcija zvoka, nizkofrekvenčno območje, časovno-frekvenčna metoda, metoda končnih elementov, upadni čas, karakterizacija materialov

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P2-0401
• Name: Energetsko strojništvo