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bioRxiv · 10.1101/2022.06.14.496157

Understanding the Dynamics of Fluid-Structure Interaction with an Air Deflected Microfluidic Chip (ADMC)

Abstract

A deformable microfluidic system and a fluidic dynamic model have been successfully coupled to understand the dynamic fluid-structure interaction in transient flow, designed to understand the dentine hypersensitivity caused by hydrodynamic theory. The Polydimethylsiloxane thin sidewalls of the microfluidic chip are deformed with air pressure ranging from 50 to 500 mbar to move the liquid meniscus in the central liquid channel. The displacement is recorded and compared with our new theoretical model derived from the unsteady Bernoulli equation. We show that our theoretical model can well predict the ending point of the liquid displacement as well as the dynamics process, regardless of the wall thickness. Moreover, an overshooting and oscillation phenomenon is observed by reducing the friction factor by a few orders which could be the key to explain the dentine hypersensitivity caused by the liquid movement in the dentine tubules.

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ten Pas, C., Du, K., Wang, R.-Q., Pan, L., Xu, S.. 2022-06-17. Understanding the Dynamics of Fluid-Structure Interaction with an Air Deflected Microfluidic Chip (ADMC). https://doi.org/10.1101/2022.06.14.496157

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