Transmission loss measurement of recycled granular material using wave decomposition by impulse response extraction based on deconvolution

Železnik, Anže (avtor), Murovec, Jure (avtor), Čurović, Luka (avtor), Cerkovnik, Nejc (avtor), Prezelj, Jurij (avtor)

A simplified method for measuring transmission loss with a single fixed microphone inside an impedance tube is proposed. The separation of the incident wave from the reflected wave is achieved by deconvolving the loudspeaker driver voltage signal with the microphone signal to extract the impulse response. Random noise and a sinusoidal sweep signal were used as excitation signals for extraction of the impulse response, and two deconvolution methods were employed: linear deconvolution based on the adaptive LMS algorithm and simple spectral division. To avoid the overlap of incident and reflected pulses, a long impedance tube was used. Using a long impedance tube eliminates the need for an anechoic tube termination and the need to calibrate microphones. It is found that a reflective tube termination provides more accurate results compared to an approximately anechoic termination. The approximately anechoic termination shortens the available time window of the reflected pulse because it reflects some of the low-frequency sound. The standard deviation of the results and the dynamic range of the proposed method were determined experimentally. The applicability of the new method was tested on samples of unconsolidated granular material recycled from construction sites. The measured transmission losses of the different granular fractions were compared with a theoretical model for transmission losses at low frequencies. Samples consisting of smaller granule fractions were found to have surprisingly high transmission loss values. The design of the extended vertical impedance tube in combination with the proposed method is cost effective, speeds up the measurement procedure and provides reliable results.

• Jezik: Angleški jezik
• Ključne besede: transmission loss, impedance tube, pulse separation, wave decomposition, deconvolution, granular materials
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FS - Fakulteta za strojništvo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2023
• Št. strani: 10 str.
• Številčenje: Vol. 211, art. 109498
• PID: 20.500.12556/RUL-149724
• UDK: 534:62-492
• ISSN pri članku: 0003-682X
• DOI: 10.1016/j.apacoust.2023.109498
• COBISS.SI-ID: 163841027
• Datum objave v RUL: 08.09.2023

Gradivo je del revije

• Naslov: Applied acoustics
• Skrajšan naslov: Appl. acoust.
• Založnik: Elsevier
• ISSN: 0003-682X
• COBISS.SI-ID: 24982016

Licence

• Licenca: CC BY-NC-ND 4.0, Creative Commons Priznanje avtorstva-Nekomercialno-Brez predelav 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by-nc-nd/4.0/deed.sl
• Opis: Najbolj omejujoča licenca Creative Commons. Uporabniki lahko prenesejo in delijo delo v nekomercialne namene in ga ne smejo uporabiti za nobene druge namene.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: prenosne izgube, impedančna cev, ločevanje pulzov, valovna dekompozicija, dekonvolucija, granulirani materiali

Projekti

• Financer: ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
• Številka projekta: P2-0401
• Naslov: Energetsko strojništvo