Navier-Stokes Simulation of the Flow Field in Laterally Driven Micro Comb Structures

摘要

Previous investigators modeled the flow field in laterally driven micro comb structures using the Couette and Stokes flow models. The quality factors predicted using these models were not in agreement with the experimental data and the reasons were not well understood. The Navier-Stokes simulation was used to study this problem. The numerical results show that if the penetration depth is larger than the gap between the fixed and oscillating structures, the flow in the gap is then indeed close to the Stokes flow. If the penetration depth is less than the gap, there is a back flow and the shear stress increases significantly. The flow above the oscillating structure is far from the Stokes flow because of the curvilinear fluid motion generated by the pumping and sucking motions of the oscillating structure. The damping predicted numerically on the top surface of the oscillating structure is much greater than that calculated using the Stokes model. The slip effects were also included in this study. The slip effects reduce the damping by about 7%.