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arXiv · 2310.01187

Fluid-structure model for disks vibrating at ultra-high frequency in a compressible viscous fluid

Hamidreza Neshasteh·Marco Ravaro·Ivan Favero
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Abstract

Radial mechanical modes of miniature disk-shaped resonators are promising candidates for probing the ultra-high-frequency rheological properties of liquids. However, the lack of an analytical fluid-structure model hinders the inference of liquid properties from the experimental measurement of such radial vibrations. Here we develop analytical models for the case of a disk vibrating in a compressible viscous liquid. Closed-form expressions for the mechanical quality factor and resonant frequency shift upon immersion are obtained, which we compare to the results of numerical modeling for a few significant cases. At frequencies above 1 GHz, our model points out the significance of compressibility effects.

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Hamidreza Neshasteh, Marco Ravaro, Ivan Favero. 2023-10-02. Fluid-structure model for disks vibrating at ultra-high frequency in a compressible viscous fluid. https://doi.org/10.1063/5.0139251

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