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arXiv · 0904.4504

Lattice Boltzmann Simulation of High-Frequency Flows: Electromechanical Resonators in Gaseous Media

Carlos Colosqui·Devrez M. Karabacak·Kamil L. Ekinci·Victor Yakhot
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Abstract

In this work, we employ a kinetic theory based approach to predict the hydrodynamic forces on electromechanical resonators operating in gaseous media. Using the Boltzmann-BGK equation, we investigate the influence of the resonator geometry on the fluid resistance in the entire range of nondimensional frequency variation $0\leτω\le\infty$; here the fluid relaxation time $τ=μ/p$ is determined by the gas viscosity $μ$ and pressure $p$ at thermodynamic equilibrium, and $ω$ is the (angular) oscillation frequency. Our results support the experimentally observed transition from viscous to viscoelastic flow in simple gases at $τω\approx1$. They are also in remarkable agreement with the measured geometric effects in resonators in a broad linear dimension, frequency, and pressure range.

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Carlos Colosqui, Devrez M. Karabacak, Kamil L. Ekinci, Victor Yakhot. 2009-04-28. Lattice Boltzmann Simulation of High-Frequency Flows: Electromechanical Resonators in Gaseous Media. https://doi.org/10.1017/s0022112010000042

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