Laboratório de Vibrações e Acústica, Departamento de Engenharia Mecânica, Universidade Federal de Santa Catarina, Campus Trindade, Florianópolis, Santa Catarina 88040-900, Brazil.
J Acoust Soc Am. 2011 Jul;130(1):EL25-31. doi: 10.1121/1.3601882.
The pressure-particle velocity (PU) impedance measurement technique is an experimental method used to measure the surface impedance and the absorption coefficient of acoustic samples in situ or under free-field conditions. In this paper, the measurement uncertainty of the the absorption coefficient determined using the PU technique is explored applying the Monte Carlo method. It is shown that because of the uncertainty, it is particularly difficult to measure samples with low absorption and that difficulties associated with the localization of the acoustic centers of the sound source and the PU sensor affect the quality of the measurement roughly to the same extent as the errors in the transfer function between pressure and particle velocity do.
压力-粒子速度(PU)阻抗测量技术是一种实验方法,用于原位或在自由场条件下测量声样本的表面阻抗和吸声系数。本文应用蒙特卡罗方法探讨了 PU 技术确定的吸声系数的测量不确定度。结果表明,由于不确定度的影响,测量低吸声系数的样本尤其困难,并且声源和 PU 传感器的声学中心定位的不确定性对测量质量的影响与压力和粒子速度之间传递函数的误差大致相同。