A Comparative Study of Thin-Film and Reynolds Equation Simulation Models for Squeeze Film Damping in MEMS Plate Structures

Abstract:

Squeeze film damping effect of MEMS parallel plate structure was analyzed based on thin film and Reynolds Equation in ANSYS under the different Knudsen numbers. Perforation effect of parallel plate with certain size and operating frequency was achieved under the different Knudsen numbers, the simulation results of two methods are very close. For unperforated plate, when Knudsen number is below 0.01, the discrepancy of two simulations is nonsignificant, and it grows up with Knudsen number. But gas rarefaction effects related with Knudsen number was considered in heat transfer analogy theory and used viscosity modification according to Veijola model, two simulations get the same result. For perforated plate, the simulation discrepancy of two methods will be great because of channel flow's effect and also grow up with Knudsen number, it can't be avoided even if the channel flow's effect and viscosity modification were concerned in heat transfer analogy theory.

• Periodical: Advanced Materials Research (Volumes 403-408)
• Pages: 4580-4587
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.403-408.4580
• Online since: November 2011
• Authors: Wei Guo Liu, Wei Wang, Shou Jun Peng
• Keywords: Knudsen Number, MEMS Plat, Reynolds Equation, Squeeze Film Damping

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