A Simple Model for the In-plane Rotational Response of a Disk Resonator in Liquid: Resonant Frequency, Quality Factor, and Optimal Geometry
Year: 2013
Type: article
Abstract: Introduction and Motivation: Micromechanical resonators have a wide variety of applications, including biological and chemical sensing, which often require the device to operate in a viscous liquid environment in which energy dissipation and fluid inertia play a key role in the device’s performance. Therefore, many investigations of MEMS resonators in liquids have focused on how to improve the quality factor (Q) by reducing energy losses to the surroundings through the use of new device geometries or unconventional modes. In the present study we explore potential advantages of an “all-shear interaction device” (ASID), consisting of a microdisk supported by two tangentially oriented microcantilevers, or “legs” (Fig. 1a). When the device is excited by imparting a harmonic axial strain to the legs (e.g., via electrothermal actuation), an in-plane rotational oscillation of the disk will ensue. This mode of vibration will engage the fluid only through shear-type interaction, as the motions of all surfaces of the ASID will have no normal component – hence, our use of the term “all-shear interaction device.” This type of interaction is expected to minimize fluid motion and, thus, viscous dissipation and fluid inertial forces, thereby yielding higher values of resonant frequency and Q in liquids. Another advantage of the ASID in sensors applications is the potentially large functionalized surface area afforded by the disk. To investigate the potential advantages of such a device and the effects of system parameters on the resonant behavior, a simple theoretical model is developed herein to quantify the damped “eigenproperties” of the system. More specif-
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2124137006