Development of Empirical Models of Polyfelt Fibrous Materials for Acoustical Applications


(*) Corresponding author


Authors' affiliations


DOI's assignment:
the author of the article can submit here a request for assignment of a DOI number to this resource!
Cost of the service: euros 10,00 (for a DOI)

Abstract


In this study, new empirical models for predicting the airflow resistivity, sound absorption coefficient of polyfelt fibrous materials have been developed. The empirical models were presented as simple power-relations by least square best fitting method of impedance tube and flow bench test data over a set of 14 samples. Two coefficients were identified for a new empirical formula to predict the airflow resistivity from the mass density and thickness of polyfelt materials and eight coefficients were identified for a new empirical formula to predict the characteristic acoustic impedance, propagation coefficients and sound absorption coefficient from the airflow resistivity. For the given mass density and thickness of a polyfelt fibrous material, the outcome proposed in this paper enables a quick and accurate evaluation of the acoustic properties of the material such as the airflow resistivity and sound absorption coefficient without a further requirement of flow bench and impedance tube tests. This is because that the predicted results from the new empirical models are closer to the measured results in the frequency range of interest than the other models in the previous work in the published literatures.
Copyright © 2013 Praise Worthy Prize - All rights reserved.

Keywords


Polyfelt Fibrous Materials; Absorption Coefficient; Characteristic Acoustic Impedance; Propagation Coefficient; Airflow Resistivity

Full Text:

PDF


References


M. Delany, E. Bazley, Acoustical Properties of Fibrous Acoustical materials, Applied Acoustics, Vol. 3, pp. 105-116, 1970.

R. Del Ray, J. Alba, J. P. Arenas, and V. J. Sanchis, An empirical modelling of porous sound absorbing materials made of recycled foam, Applied Acoustics, Vol.73 (6-7), 604-609, 2012.

M.H. Fouladi, MD. Ayub, MJ. Mohd nor, Analysis of coir fiber acoustical characteristics, Applied Acoustics, Vol. 72, pp. 35-42, 2011.

D. Bies, C. Hansen, Flow Resistance Information for Acoustical Design, Applied Acoustics, Vol. 13, pp. 357-391, 1980.

I. P. Dunn, W. A. Davern, Calculation of Acoustic Impedance of Multi-layer Absorbers, Applied Acoustics, Vol. 19, pp. 321-334, 1986.

Q. Wu, Empirical Relations between Acoustical Properties and Flow resistivity of Porous Plastic Open-cell Foam, Applied Acoustics, Vol. 25, pp. 141-148, 1988.

Y. Miki, Acoustical properties of porous materials-Modification of Delany – Bazley models, J. Acoust. Soc. Japan, Vol. 11, pp. 19-28, 1990.

J.F. Allard, Y. Champoux, New empirical equations for sound propagation in rigid frame fibrous materials, Journal of the Acoustical Society of America, Vol.91, pp.3346–3353, 1992.

N. Voronina, Acoustic properties of Fibrous materials, Applied Acoustics, Vol. 42, pp. 165-174, 1994.

N. Voronina, An empirical model for rigid frame porous materials with high Porosity, Applied Acoustics, Vol.51, pp.181–98, 1997.

G.C. Gardner, M. E. O’Leary, S. Hansen, J. Q. Sun, Neural network for prediction of acoustical properties of polyurethane foams, Applied Acoustics, Vol. 64, No.2, 229–42, 2003.

D.K. Wilson, Simple, Relaxation Models for the Acoustical Properties of Porous Media, Applied Acoustics, Vol. 50, No. 3, pp. 171-188, 1997.

M.A. Biot, Theory of propagation of elastic waves in a fluid saturated porous solid. I. Low-frequency range, Journal of the Acoustical Society of America, Vol.28, No.2, pp.168–178, 1956.

D.L. Johnson, J. Koplik, R. Dashen, Theory of dynamic permeability and tortuosity in fluid-saturated porous media, Journal of Fluid Mechanics, Vol.176, pp.379–402, 1987.

C. Zwikker and C.W. Kosten, Sound absorbing materials, Elsevier, New York, 1949.

Y. Champoux, J. F. Allard, Dynamic tortuosity and bulk modulus in air-saturated porous media, Journal of Applied Physics, Vol.70, pp. 1975-1979, 1991.

S. R. Pride, F. D. Morgan, F. A. Gangi, Drag forces of porous media acoustics, Physical Review B 47, pp. 4964-4975. 1993

K. Attenborough, Acoustical characteristics of porous materials, Physics reports, Vol. 82, pp.179-227, 1982.

K. Attenborough, Acoustical characteristics of rigid fibrous absorbents and granular materials, Journal of the Acoustical Society of America, Vol. 73:785–799, 1983.

Y. Champoux, M. R. Stinson, Experimental investigation of models of sound wave propagation in air saturated porous media, Journal of the Acoustical Society of America, Vol.88 (Suppl.):121, 1990.

ASTM C522-03, Acoustics-materials for acoustical applications-determination of airflow resistance, 2003.

ASTM E1050-08, Standard test method for Impedance and Absorption of Acoustical Materials using a Tube, Two Microphones and A Digital frequency Analysis System, 2008.

H. Utsuno, T. Tanaka, T. Fujikawa, A. F. Seybert, Transfer function method for measuring characteristic impedance and propagation constant of porous materials, J Acoust Soc Am, Vol. 86, pp. 637-643. 1989.

M. Garai, F. Pompoli, A simple empirical model of polyester fibre materials for acoustical applications, Applied Acoustics, Vol.66, pp. 1383-1398, 2005.

M. K. Ling, Technical note-Impedance of polyurethane foams, Appl. Acoust., Vol. 34, pp. 221-224, 1991.

D.A. Bies, and C. H. Hansen, Engineering noise control: Theory and practice, Fourth ed., Spon press, London and New York.2009.

T. Komatsu, improvement of the Delany - Bazley and Miki models for fibrous sound absorbing materials, Acoust. Sci. & Tech., Vol. 29(2), pp. 121-129, 2008.


Refbacks

  • There are currently no refbacks.


Please send any question about this web site to info@praiseworthyprize.com
Copyright © 2005-2024 Praise Worthy Prize