含主动耳蜗的人耳传声有限元模拟

FE simulation of sound transmission in human ear with an active cochlea model

采用外耳道、中耳、简化耳蜗耦合的有限元模型,模拟声压从外耳道传入耳蜗和耳蜗液体驱动基底膜振动的过程。耳蜗模型包含正交各向异性材料基底膜并考虑尺寸和材料性质沿长度的变化,在对柯蒂氏器进行微观力学分析的基础上,运用前馈模型实现耳蜗的主动机制。提出外耳道声音激励与耳蜗主动机制联合作用下中耳和耳蜗响应计算方法,结果表明:该模型实现了外耳道激励下基底膜位移与激励水平的非线性、基底膜频率选择等特性的模拟。

A finite element model integrating ear canal, middle ear and cochlea was established and used to simulate a process of sound transmission from ear canal to cochlea, and cochlear fluid driving basilar membrane to vibrate. The cochlea model included an orthotropic basilar membrane with dimensional and material property variation along its length. Based on the micro-mechanic analysis of organ of Corti, a feed-forward mechanism was used to realize the cochlea active amplifier features. A numerical method, combining ear canal stimuli and cochlea active mechanism, was developed to compute the responses in the middle ear and active cochlea. The results showed that the model achieves basilar membrane response level compression and frequency selectivity characteristics with respect to ear canal sound stimuli.