Near-contact damping model and dynamic response of μ-beams under high-g loads

This paper presents the first near-contact aerodynamic damping model based on rarefied flow modeling for use in dynamic simulations of large-displacement motion and contacting behavior of microbeams. The damping model is constructed based on high-fidelity simulations of rarefied gas flow around microbeams based on the Boltzmann kinetic equation with the Ellipsoidal Statistical Bhatnagar-Gross-Krook (ES-BGK) collision relaxation model. The predictions using the new model and previously published models are compared with experimentally measured responses of silicon microbeams under a high-g dynamic load. The new model is validated by measuring the near-contact behavior of silicon microbeams under loads up to 52,500 g and with ramping rates up to 2,750 g/μs. The model and experiments were found to be in close agreement with a maximum variation of less than 13.1%.