Compact Analytical Model of Squeeze-Film Damping Considering Slip Boundary Conditions in Perforated MEMS Structures

A compact analytical model of squeeze-film damping in perforated MEMS plates was presented. The compact analytical model took several factors into consideration, including the rarefaction of the air flow,the pressure loss caused by perforating and the air shear force formed on the inner wall. The perforated plate was divided into several identical circular cells. The pressure distribution in each circular cell was obtained through a modified Reynolds equation. The rarefaction effect of air flow was explained by considering the slip boundary conditions. The loss of pressure because of perforating was determined according to the conservation of air flow. The compact analytical model was compared with Kwok's analytical model, Veijola's analytical model and the experiment results obtained by Pasquale respectively in order to verify the correctness of the theoretical model. The results indicate that the compact analytical model presented in this paper computes more accurately than Kwok's model and more conveniently than Veijola's model.