Presentazioni e Articoli Tecnici

The present paper describes the results of a Finite Element Model used to analyze sound propagation in lined ducts. By means of a numerical model it was possible to predict the insertion loss inside rectangular lined ducts in a frequency range from 250 Hz to 4000 Hz. The model was validated by a comparison with experimental data obtained in accordance to ISO 11691 and ISO 7235 standards. The sound absorbing material for the lining was mineral wool, whose thickness was varied from 25 mm to 150 mm. Comparisons showed a good accordance between experimental and numerical data, suggesting that FEM (Finite Element Method) can be an accurate and inexpensive way to predict sound attenuation in lined ducts.