Fluid-structure interaction analysis of traveling waves propagating on an artificial cochlear sensory epithelium

Abstract

In this paper, oscillations of an artificial sensory epithelium located in the cochlea filled with lymph fluids are simulated by a finite element method. The artificial cochlear sensory epithelium is a trapezoidal piezoelectric membrane to mimic functions of the cochlea, and these physical properties using in the numerical analysis are estimated based on experimental results. The artificial cochlear sensory epithelium is set into the model straightened-cochlea filled with a fluid, and an oscillation is induced by mimicking a transmission of the biological cochlea. Normal frequencies and modes of the artificial cochlear sensory epithelium are well simulated to represent the frequency selectivity of the biological basilar membrane. The Euler-Bernoulli theory for transvers vibrations of a beam successfully predicts normal frequencies when the trapezoidal membrane is modeled as a set of fixed-end beams. Moreover, traveling waves propagating on the artificial cochlear sensory epithelium are numerically and successfully observed in the present study. That is, not only structure but also critical feature of the biological cochlea is represented by an artificial mechanical system.