Physikalisch-Technische Bundesanstalt, Braunschweig, Germany.
J Acoust Soc Am. 2012 Jul;132(1):EL8-14. doi: 10.1121/1.4723565.
Many ear canal probes both deliver and measure sound via narrow tubes. This study investigates the effect of the cross-sectional discontinuity at the interface between ear canal models and the connecting tubes of a commercially available otoacoustic emission probe on the "acoustically" estimated cavity lengths. Rigid cavities having the same length but different diameters were produced, and modeled by the finite element method. Cavities with a diameter larger than 8 mm had acoustic lengths that considerably overestimated the real geometry. A length correction was derived, which, in most applications, compensates for the measurement errors emerging from the discontinuity effects.
许多耳道探头既能传输声音，也能通过细管测量声音。本研究探讨了在商用耳声发射探头的耳道模型与连接管的界面处的横截面积不连续对“声学”估计腔长的影响。制作了具有相同长度但不同直径的刚性腔，并通过有限元法对其进行了建模。直径大于 8 毫米的腔的声学长度大大高估了实际几何形状。推导了一个长度修正值，该值在大多数应用中可以补偿由于不连续性效应而产生的测量误差。
