Abstract
In this paper, squeeze film damping in a micro-beam resonator based on micro-polar theory has been investigated. The proposed model for this study consists of a clamped-clamped micro-beam bounded between two fixed layers. The gap between the micro-beam and layers is filled with air. As fluid behaves differently in micro scale than macro, the micro-scale fluid field in the gap has been modeled based on micro-polar theory. Equation of motion governing transverse deflection of the micro- beam based on modified couple stress theory and also non-linear Reynolds equation of the fluid field based on micropolar theory have been non-dimensionalized, linearized and solved simultaneously in order to calculate the quality factor of the resonator. The effect of micropolar parameters of air on the quality factor has been investigated. The quality factor of the of the micro-beam resonator for different values of non-dimensionalized length scale of the beam, squeeze number and also non-dimensionalized pressure has been calculated and compared to the obtained values of quality factor based on classical theory.
Highlights
Progress in technology of micro-electromechanical systems (MEMS) can be seen in fabricating new devices and creating innovative applications
78 Mina Ghanbari et al / Study of Squeeze Film Damping in a Micro-beam Resonator Based on Micro-Polar Theory hod because of inherent couple-energy domains as electrostatic, thermal and mechanical forces involved in designe process
4 CONCLUSIONS In this paper, squeeze film damping in the micro-beam resonator was studied
Summary
Progress in technology of micro-electromechanical systems (MEMS) can be seen in fabricating new devices and creating innovative applications. 78 Mina Ghanbari et al / Study of Squeeze Film Damping in a Micro-beam Resonator Based on Micro-Polar Theory hod because of inherent couple-energy domains as electrostatic, thermal and mechanical forces involved in designe process. Several studies have been done on the dynamic behavior of the micro-structures under squeeze film damping but most of them have used the linearized Reynolds equation obtained by classical theories, for simulating the fluid field. The coupled governing equations of motion of the beam based on modified couple stress theory and pressure field of the fluid based on micro-polar theory are solved simultaneously using Galerkin based reduced order model. Eringen (1968) introduced the concept of micro-polar fluids to characterize concentrated suspensions of neutrally buoyant rigid particles in a viscous fluid where individuality of substructures affects the physical outcome of the flow These fluids support couple stresses and body couples they exhibit micro-rotational and micro-inertial effects. It may be noted that micropolar fluid theory takes care of the rotation of fluid particles by means of a kinematic vector called the micro-rotation vector which is independent from the vorticity of the fluid and is absent in classical continuum
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
