Wagemann, Enrique

Walther, Jens Honore

Zambrano, Harvey

Transport of water in hydrophilic nanopores is of significant technological and scientific interest. Water flow through hydrophilic nanochannelsis known to experience enormous hydraulic resistance. Therefore, drag reduction is essential for the development of highly efficient nanofluidic devices. In this work, we propose the use of graphitic materials as wall coatings in hydrophilic silica nanopores. Specifically, by conducting atomistic simulations, we investigate the flow inside slit and cylindrical silica channels with walls coated with graphene (GE) layers and carbonnanotubes (CNTs), respectively. We develop realistic force fields to simulate the systems of interest and systematically, compare flow rates in coated and uncoated nanochannels under different pressure gradients. Moreover, we assess the effect that GE and CNT translucencies to wettability have on water hydrodynamics in the nanochannels. The influence of channel size is investigated by systematically varying channel heights and nanopore diameters. In particular, we present the computed water density and velocity profiles, volumetric flow rates, slip lengths and flow enhancements, to clearly demonstrate the drag reduction capabilities of graphitic wall coatings

Online Research Database In Technology

                       General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.  • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal   If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.     Downloaded from orbit.dtu.dk on: Dec 16, 2017Drag reduction in silica nanochannels induced by graphitic wall coatingsWagemann, Enrique; Walther, Jens Honore; Zambrano, HarveyPublication date:2017Document VersionPublisher's PDF, also known as Version of recordLink back to DTU OrbitCitation (APA):Wagemann, E., Walther, J. H., & Zambrano, H. (2017). Drag reduction in silica nanochannels induced bygraphitic wall coatings. Abstract from 70th Annual Meeting of the American Physical Society Division of FluidDynamics (DFD17), Denver, United States.Abstract Submittedfor the DFD17 Meeting ofThe American Physical SocietyDrag reduction in silica nanochannels induced by graphiticwall coatings.1 ENRIQUE WAGEMANN, Universidad de Concepcion, J. H.WALTHER, Technical University of Denmark, HARVEY A. ZAMBRANO, Univer-sidad de Concepcion | Transport of water in hydrophilic nanopores is of signicanttechnological and scientic interest. Water ow through hydrophilic nanochannelsis known to experience enormous hydraulic resistance. Therefore, drag reduction isessential for the development of highly ecient nanouidic devices. In this work, wepropose the use of graphitic materials as wall coatings in hydrophilic silica nanopores.Specically, by conducting atomistic simulations, we investigate the ow inside slitand cylindrical silica channels with walls coated with graphene (GE) layers and car-bon nanotubes (CNTs), respectively. We develop realistic force elds to simulate thesystems of interest and systematically, compare ow rates in coated and uncoatednanochannels under dierent pressure gradients. Moreover, we assess the eect thatGE and CNT translucencies to wettability have on water hydrodynamics in thenanochannels. The inuence of channel size is investigated by systematically vary-ing channel heights and nanopore diameters. In particular, we present the computedwater density and velocity proles, volumetric ow rates, slip lengths and ow en-hancements, to clearly demonstrate the drag reduction capabilities of graphitic wallcoatings.1We wish to thank partial funding from CRHIAM Conicyt/ Fondap Project15130015 and computational support from DTU and NLHPC (Chile).Enrique WagemannUniversidad de ConcepcionDate submitted: 14 Jun 2017 Electronic form version 1.4

Drag reduction in silica nanochannels induced by graphitic wall coatings

http://orbit.dtu.dk/ws/files/139802878/MWS_DFD17_2017_000016.pdf

Drag reduction in silica nanochannels induced by graphitic wall coatings

Abstract

Similar works

Full text

Available Versions

Online Research Database In Technology