The effect of squeeze-film damping on the shock response of clamped-clamped microbeams

This paper presents an investigation into the nonlinear effect of squeeze-film damping on the response of a clamped-clamped microbeam to mechanical shock. In this work, we solve simultaneously the nonlinear Reynolds equation, to model squeeze-film damping, coupled with a nonlinear Euler-Bernoulli beam equation. A Galerkin-based reduced-order model and a finite-difference method are utilized for the solid domain and fluid domain, respectively. Several results demonstrating the effect of gas pressure on the response of the microbeams are shown. Comparison with the results of a fully coupled multiphysics nonlinear finite-element model is presented. The results indicate that, for devices operating in air, squeeze-film damping can be used effectively to minimize the displacements of released microstructures during shock and impact. The results also indicate that squeeze-film damping has more significant effect on the response of microstructures in the dynamic shock regime compared to the quasi-static shock regime. A computationally efficient approach is proposed to model the fluidic-structural problem more efficiently based on a nonlinear analytical expression of the squeeze-film damping.