Method of Testing of Sound Absorption Properties of Materials Intended for Ultrasonic Noise Protection

• Autorzy: Pleban D.
• Języki publikacji: EN

Abstrakty

EN

Efficient ultrasonic noise reduction by using enclosures requires the knowledge of absorbing properties of materials in the frequency range above 4 kHz. However, standardized methods enable determination of absorption coefficients of materials in the frequency range up to 4 kHz. For this reason, it is proposed to carry out measurements of the sound absorption properties of materials in the free field by means of a tone-burst technique in the frequency range from 4 kHz to 40 kHz at angles of incidence varying from 0° to 60°. The absorption coefficient of a material is calculated from the reflection coefficient obtained by reflecting a tone-burst from both a perfectly reflecting panel and a combination of this panel and the sample of the tested material. The tests results show that mineral wool and polyurethane open-cell foam possess very good absorbing properties in this frequency range.

Słowa kluczowe

EN

ultrasonic noise; sound absorption coefficient; tone burst technique; sound absorbing material

• Wydawca: Instytut Podstawowych Problemów Techniki PAN ; Komitet Akustyki PAN ; Polskie Towarzystwo Akustyczne
• Czasopismo: Archives of Acoustics
• Rocznik: 2013
• Tom: Vol. 38, No. 2
• Strony: 191--195
• Opis fizyczny: Bibliogr. 12 poz., wykr.

Twórcy

autor

Pleban D.

• Central Institute for Labour Protection – National Research Institute Czerniakowska 16, 00-701 Warszawa, Poland

Bibliografia

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