Huang Jie, Feng Xuelei, Chen Simiao, Shen Yong
Key Laboratory of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093, China.
J Acoust Soc Am. 2021 Mar;149(3):1579. doi: 10.1121/10.0003644.
Total harmonic distortion (THD) plays an important role in the performance of miniature loudspeakers used in mobile phones. Traditional nonlinear models fail to predict THD in the higher frequency domain. Significant discrepancies can be found between the prediction and measurement. In this study, an extended model considering nonlinear acoustic damping is proposed to address this issue. Flow separation occurring near the orifices of the sound port is of particular interest. Two velocity-dependent parameters were derived to model the nonlinear damping effect. Based on the extended model, the dynamics of miniature loudspeakers are described using the state-space method. Experiments and calculations confirm the validity of the extended model. The influence of nonlinear acoustic damping on THD is also discussed.
总谐波失真（THD）在手机中使用的微型扬声器性能中起着重要作用。传统的非线性模型无法预测高频域中的THD。在预测和测量之间可以发现显著差异。在本研究中，提出了一种考虑非线性声阻尼的扩展模型来解决这个问题。特别关注声端口孔口附近发生的流动分离。推导了两个与速度相关的参数来模拟非线性阻尼效应。基于扩展模型，使用状态空间方法描述了微型扬声器的动力学。实验和计算证实了扩展模型的有效性。还讨论了非线性声阻尼对THD的影响。
