THURSDAY MORNING, 3 JULY 2008 ROOM 242B, 8:00 A.M. TO 12:00 NOON Session 4aAAa Architectural Acoustics: Architectural Acoustics Potpourri David T. Bradley, Cochair 124 Raymond Avenue, Poughkeepsie, NY, 12604 Andrea Farnetani, Cochair Engineering Dept. - Univ. of Ferrara, Via Saragat, 1, Ferrara, 44100, Italy Contributed Papers 8:00 8:40 4aAAa1. Irregular sound absorbers work better. Bernard 4aAAa3. The vibration sound absorption theory of soft materials.Xin Sapoval ͑Ecole Polytechnique, PMC-Polytechnique Route de Saclay, An Zhang ͑Xi’an Polytechnic University, 134#, Key Laboratary, 19 South 91128 Palaiseau, France,
[email protected]͒, Anna Jin Hua Road, 710048 Xi’an, China,
[email protected]͒ Rozanova-Pierrat ͑Ecole Polytechnique, PMC-Polytechnique Route de During the past 2 years, a new theory has been established for soft ma- Saclay, 91128 Palaiseau, France, anna.rozanova-pierrat@polytechnique terials that the vibration of materials brings the sound absorption, regardless ͒ ͑ .edu , Simon Félix Laboratoire d’Acoustique de l’Université du Maine, whether they have pores in them or not. This theory is totally different from Avenue Olivier Messiaen, 72085 Le Mans, France, simon.felix@univ- Classical theory, such as the Rayleigh model and the Zwikker and Kosten lemans.fr͒, Marcel Filoche ͑Ecole Polytechnique, PMC-Polytechnique theory. Firstly, an empirical sound absorption coefficients formula of fibrous Route de Saclay, 91128 Palaiseau, France, marcel.filoche@polytechnique materials was found. Secondly, the theory sound absorption formula of thin .edu͒ fiber layers was obtained by the vibration sound absorption analysis and the applying of conservation law of energy. This formula agrees well with the The diffraction and absorption of waves by a system with both absorbing empirical sound absorption formula of fibrous materials ͑mentioned above͒.