We present results from a series of compute-intensive simulation experiments employing a realistic and detailed three-dimensional model of the human cochlear macro-mechanics. Our model uses the immersed boundary method to compute the fluid-structure interactions within the cochlea. It is a three-dimensional model based on an accurate cochlear geometry obtained from physical measurements. It includes detailed descriptions of the elastic material components immersed in the fluid, and is based on the previously developed immersed boundary method for elastic shells. The basilar membrane is modeled by a fourth-order partial differential equation of shell theory. The results reproduce the basic well known characteristics of cochlear mechanics and constitute a successful initial step in model validation