Alexandria Digital Research Library

Channel deformation in electrokinetic micro- and nanofluidic systems

Author:
Rutte, Joseph Michael de
Degree Grantor:
University of California, Santa Barbara. Mechanical Engineering
Degree Supervisor:
Sumita Pennathur
Place of Publication:
[Santa Barbara, Calif.]
Publisher:
University of California, Santa Barbara
Creation Date:
2016
Issued Date:
2016
Topics:
Mechanical engineering and Nanoscience
Keywords:
Electrokinetics
Nanofluidics
Microfluidics
Deformation
Genres:
Dissertations, Academic and Online resources
Dissertation:
M.S.--University of California, Santa Barbara, 2016
Description:

Large pressures can induce detrimental deformation in micro- and nanofluidic channels. Although this has been extensively studied for systems driven by pressure and/or capillary forces, deflection in electrokinetic systems due to internal pressure gradients caused by nonuniform electric fields has not been widely explored. For example, applying an axial electric field in a channel with a step change in conductivity and/or surface charge can lead to internally generated pressures large enough to cause cavitation, debonding, and/or channel collapse. Finite electric double layers within nanofluidic channels can further complicate the physics involved in the deformation process. In order to design devices and experimental procedures that avoid issues resulting from such deformation it is imperative to be able to predict deformation for given system parameters. In this work, we analytically and numerically investigate pressures resulting from a step change in conductivity and/or surface charge in micro and nanofluidic channels with both thin and thick double layers. We show an explicit relation of pressure dependence on concentration ratio and electric double layer thickness. Furthermore, we develop a numerical model to predict deformation in such systems and use the model to unearth trends in deformation for various electric double layer thicknesses and both glass and PDMS on glass channels. Our work is particularly impactful for the development and design of micro- and nanofluidic-based devices with gradients in surface charge and/or conductivity, fundamental study of electrokinetic-based cavitation, and other systems that exploit nonuniform electric fields.

Physical Description:
1 online resource (73 pages)
Format:
Text
Collection(s):
UCSB electronic theses and dissertations
ARK:
ark:/48907/f3hq4023
ISBN:
9781369340198
Catalog System Number:
990047190260203776
Rights:
Inc.icon only.dark In Copyright
Copyright Holder:
Joseph de Rutte
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