FLUID MECHANICS IN THE SUBTECTORIAL SPACE

In the subtectorial space, momentum is transported by the fluid to the stereocilia of the inner hair cell (IHC), resulting in bending of the hair bundle. The fluid must pass through the v-shaped arrangement of the outer hair cell (OHC) stereocilia and is "squeezed" between the tectorial membrane (TM) and the reticular lamina, especially due to the Hensen's stripe. Here, we analyze the flow field by means of numerical discretization. Since the geometry is complex, the finite-element-method is employed. An implementation is developed which allows computation in the frequency domain, based on a pressure stabilised velocity formulation. Matrix coupling with the structure is accomplished and a single solution step of the whole system matrix is sufficient to retrieve the displacement field of the fluid and structural parts. The proposed method allows a solution of the fluid-structure interaction in the subtectorial space within a reasonable time. For a two-dimensional mesh with 120,000 degrees of freedom of a complete cross-section of the organ of Corti, including stereocilia, the solution time is less than 20 seconds on a convential PC.