Abstract
Sound absorption coefficients of various powder beds comprised of binary powder mixtures were measured using an acoustic tube, and the longitudinal elastic coefficients of the powder beds were obtained from the absorption peak frequencies. It was found that the longitudinal elastic coefficient of the powder mixture bed in an almost naturally packed state can be estimated from the respective longitudinal elastic coefficient and volume ratios of the constituent powder materials. This indicates the possibility of designing new sound-absorbing materials to suit the characteristics of the noise source.
