@article{c10db4f76f5143a49d25adff5926b770,
title = "Viscous flow through microfabricated axisymmetric contraction/expansion geometries",
abstract = "Abstract: We employ a state-of-the-art microfabrication technique (selective laser-induced etching) to fabricate a set of axisymmetric microfluidic geometries featuring a 4:1 contraction followed by a 1:4 downstream expansion in the radial dimension. Three devices are fabricated: the first has a sudden contraction followed by a sudden expansion, the second features hyperbolic contraction and expansion profiles, and the third has a numerically optimized contraction/expansion profile intended to provide a constant extensional/compressional rate along the axis. We use micro-particle image velocimetry to study the creeping flow of a Newtonian fluid through the three devices and we compare the obtained velocity profiles with finite-volume numerical predictions, with good agreement. This work demonstrates the capability of this new microfabrication technique for producing accurate non-planar microfluidic geometries with complex shapes and with sufficient clarity for optical probes. The axisymmetric microfluidic geometries examined have potential to be used for the study of the extensional properties and non-linear dynamics of viscoelastic flows, and to investigate the transport and deformation dynamics of bubbles, drops, cells, and fibers. Graphic abstract: [Figure not available: see fulltext.]",
author = "Francisco Pimenta and Kazumi Toda-Peters and Shen, {Amy Q.} and Alves, {Manuel A.} and Haward, {Simon J.}",
note = "Funding Information: FP and MMA acknowledge funding from Funda{\c c}{\~a}o para a Ci{\^e}ncia e a Tecnologia (UIDB/00532/2020). KT-P, AQS, and SJH gratefully acknowledge the support of the Okinawa Institute of Science and Technology Graduate University (OIST) with subsidy funding from the Cabinet Office, Government of Japan. A.Q.S. and S.J.H. also acknowledge funding from the Japan Society for the Promotion of Science (Kakenhi Grant Nos. 18K03958 and 18H01135) and the Joint Research Projects (JRPs) supported by JSPS and SNSF. We thank the OIST Imaging Section for providing access to the Zeiss Xradia 510 Versa -CT scanning instrument and Dr. Shinya Komoto for related technical support. Funding Information: FP and MMA acknowledge funding from Funda??o para a Ci?ncia e a Tecnologia (UIDB/00532/2020). KT-P, AQS, and SJH gratefully acknowledge the support of the Okinawa Institute of Science and Technology Graduate University (OIST) with subsidy funding from the Cabinet Office, Government of Japan. A.Q.S. and S.J.H. also acknowledge funding from the Japan Society for the Promotion of Science (Kakenhi Grant Nos. 18K03958 and 18H01135) and the Joint Research Projects (JRPs) supported by JSPS and SNSF. We thank the OIST Imaging Section for providing access to the Zeiss Xradia 510 Versa ? \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mu $$\end{document} -CT scanning instrument and Dr. Shinya Komoto for related technical support. Publisher Copyright: {\textcopyright} 2020, The Author(s).",
year = "2020",
month = sep,
day = "1",
doi = "10.1007/s00348-020-03036-z",
language = "English (US)",
volume = "61",
journal = "Experiments in Fluids",
issn = "0723-4864",
publisher = "Springer Verlag",
number = "9",
}