TY  - CHAP
U1  - Konferenzveröffentlichung
A1  - Sackmann, Benjamin
A1  - Warnholtz, Birthe
A1  - Sim, Jae Hoon
A1  - Burovikhin, Dmitrii
A1  - Dalhoff, Ernst
A1  - Eberhard, Peter
A1  - Lauxmann, Michael
ED  - Kecskeméthy, Andrés
T1  - Investigation of tympanic membrane influences on middle-ear impedance measurements and simulations
T2  - Multibody dynamics 2019 : proceedings of the 9th ECCOMAS Conference on Multibody Dynamics. - (Computational methods in applied sciences ; 53)
N2  - This study simulates acoustic impedance measurements in the human ear canal and investigates error influences due to improperly accounted evanescence in the probe’s near field, cross-section area changes, curvature of the ear canal, and pressure inhomogeneities across the tympanic membrane, which arise mainly at frequencies above 10 kHz. Evanescence results from strongly damped modes of higher order, which can only be found in the near field of the sound source and are excited due to sharp cross-sectional changes as they occur at the transition from the probe loudspeaker to the ear canal. This means that different impedances are measured depending on the probe design. The influence of evanescence cannot be eliminated completely from measurements, however, it can be reduced by a probe design with larger distance between speaker and microphone. A completely different approach to account for the influence of evanescence is to evaluate impedance measurements with the help of a finite element model, which takes the precise arrangement of microphone and speaker in the measurement into account. The latter is shown in this study exemplary on impedance measurements at a tube terminated with a steel plate. Furthermore, the influences of shape changes of the tympanic membrane and ear canal curvature on impedance are investigated.
Y1  - 2020
U6  - https://doi.org/10.1007/978-3-030-23132-3_1
DO  - https://doi.org/10.1007/978-3-030-23132-3_1
SP  - 3
EP  - 10
S1  - 8
PB  - Springer
CY  - Cham
ER  -