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(2020) Role of All Jet Drops in Mass Transfer from Bursting Bubbles
PHYSICAL REVIEW FLUIDS 5, 033605 (2020) Role of all jet drops in mass transfer from bursting bubbles Alexis Berny,1,2 Luc Deike ,2,3 Thomas Séon,1 and Stéphane Popinet 1 1Sorbonne Université, CNRS, UMR 7190, Institut Jean le Rond ࢚’Alembert, F-75005 Paris, France 2Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, USA 3Princeton Environmental Institute, Princeton University, Princeton, New Jersey 08544, USA (Received 12 September 2019; accepted 13 February 2020; published 10 March 2020) When a bubble bursts at the surface of a liquid, it creates a jet that may break up and produce jet droplets. This phenomenon has motivated numerous studies due to its multiple applications, from bubbles in a glass of champagne to ocean/atmosphere interactions. We simulate the bursting of a single bubble by direct numerical simulations of the axisymmetric two-phase liquid-gas Navier-Stokes equations. We describe the number, size, and velocity of all the ejected droplets, for a wide range of control parameters, defined as nondimensional numbers, the Laplace number which compares capillary and viscous forces and the Bond number which compares gravity and capillarity. The total vertical momentum of the ejected droplets is shown to follow a simple scaling relationship with a primary dependency on the Laplace number. Through a simple evaporation model, coupled with the dynamics obtained numerically, it is shown that all the jet droplets (up to 14) produced by the bursting event must be taken into account as they all contribute to the total amount of evaporated water. A simple scaling relationship is obtained for the total amount of evaporated water as a function of the bubble size and fluid properties. -
A Novel Momentum-Conserving, Mass-Momentum Consistent Method for Interfacial flows Involving Large Density Contrasts Sagar Pal, Daniel Fuster, St´Ephanezaleski
Highlights A novel momentum-conserving, mass-momentum consistent method for interfacial flows involving large density contrasts Sagar Pal, Daniel Fuster, St´ephaneZaleski • Conservative formulation of Navier Stokes with interfaces using the Volume- of-Fluid method. • Geometrical interface and flux reconstructions on a twice finer grid en- abling discrete consistency between mass and momentum on staggered uniform Cartesian grids. • Conservative direction-split time integration of geometric fluxes in 3D, enabling discrete conservation of mass and momentum. • Quantitative comparisons with standard benchmarks for flow configura- tions involving large density contrasts. • High degree of robustness and stability for complex turbulent interfacial flows, demonstrated using the case of a falling raindrop. arXiv:2101.04142v1 [physics.comp-ph] 11 Jan 2021 A novel momentum-conserving, mass-momentum consistent method for interfacial flows involving large density contrasts Sagar Pala,∗, Daniel Fustera, St´ephaneZaleskia aInstitut Jean le Rond @'Alembert, Sorbonne Universit´eand CNRS, Paris, France Abstract We propose a novel method for the direct numerical simulation of interfacial flows involving large density contrasts, using a Volume-of-Fluid method. We employ the conservative formulation of the incompressible Navier-Stokes equa- tions for immiscible fluids in order to ensure consistency between the discrete transport of mass and momentum in both fluids. This strategy is implemented on a uniform 3D Cartesian grid with a staggered configuration of primitive vari- ables, wherein a geometrical reconstruction based mass advection is carried out on a grid twice as fine as that for the momentum. The implementation is in the spirit of Rudman (1998) [41], coupled with the extension of the direction-split time integration scheme of Weymouth & Yue (2010) [46] to that of conservative momentum transport. -
Mass Transfer with the Marangoni Effect 87 7.1 Objectives
TECHNISCHE UNIVERSITÄT MÜNCHEN Professur für Hydromechanik Numerical investigation of mass transfer at non-miscible interfaces including Marangoni force Tianshi Sun Vollständiger Abdruck der an der Ingenieurfakultät Bau Geo Umwelt der Technischen Universität Munchen zur Erlangung des akademischen Grades eines Doktor-Ingenieurs genehmigten Dissertation. Vorsitzender: Prof. Dr.-Ing. habil. F. Düddeck Prüfer der Dissertation: 1. Prof. Dr.-Ing. M. Manhart 2. Prof. Dr. J.G.M. Kuerten Die Dissertation wurde am 31. 08. 2018 bei der Technischen Universitat München eingereicht und durch die Ingenieurfakultat Bau Geo Umwelt am 11. 12. 2018 angenommen. Zusammenfassung Diese Studie untersucht den mehrphasigen Stofftransport einer nicht-wässrigen flüssigkeit ("Non-aqueous phase liquid", NAPL) im Porenmaßstab, einschließlich der Auswirkungen von Oberflachenspannungs und Marangoni-Kraften. Fur die Mehrphasensträmung wurde die Methode "Conservative Level Set" (CLS) implementiert, um die Grenzflache zu verfol gen, wahrend die Oberflachenspannungskraft mit der Methode "Sharp Surface Tension Force" (SSF) simuliert wird. Zur Messung des Kontaktwinkels zwischen der Oberflache der Flus- sigkeit und der Kontur der Kontaktflaäche wird ein auf der CLS-Methode basierendes Kon taktlinienmodell verwendet; das "Continuum Surface Force" (CSF)-Modell wird zur Model lierung des durch einen Konzentrationsgradienten induzierten Marangoni-Effekts verwendet; ein neues Stofftransfermodell, das einen Quellterm in der Konvektions-Diffusionsgleichungen verwendet, wird zur -
1.2 Porous Media Flow
Research Collection Doctoral Thesis Experimental and numerical investigation of porous media flow with regard to the emulsion process Author(s): Benedikt Hövekamp, Tobias Publication Date: 2002 Permanent Link: https://doi.org/10.3929/ethz-a-004511272 Rights / License: In Copyright - Non-Commercial Use Permitted This page was generated automatically upon download from the ETH Zurich Research Collection. For more information please consult the Terms of use. ETH Library Diss. ETH No. 14836 Experimental and Numerical Investigation of Porous Media Flow with regard to the Emulsion Process A dissertation submitted to the SWISS FEDERAL INSTITUTE OF TECHNOLOGY ZURICH¨ for the degree of Doctor of Technical Sciences presented by Tobias Benedikt Hov¨ ekamp Dipl.-Ing. born June 18, 1970 citizen of Germany accepted on the recommendation of Prof. Dr.-Ing. E. Windhab, examiner Prof. Dr. K. Feigl, co-examiner. 2002 c 2002 Tobias Hov¨ ekamp Laboratory of Food Process Engineering (ETH Zurich)¨ All rights reserved. Experimental and Numerical Investigation of Porous Media Flow with regard to the Emulsion Process ISBN: 3-905609-17-7 LMVT Volume: 16 Published and distributed by: Laboratory of Food Process Engineering Swiss Federal Institute of Technology (ETH) Zurich¨ ETH Zentrum, LFO CH-8092 Zurich Switzerland http://www.vt.ilw.agrl.ethz.ch Printed in Switzerland by: bokos druck GmbH Badenerstrasse 123a CH-8004 Zurich¨ Rien n’est plus fort qu’une idee´ dont l’heure est venue Victor Hugo To Barbara Danksagung Die vorliegende Dissertation wurde erst durch die Mithilfe und Unterstutzung¨ vieler Men- schen moglich.¨ Gerne mochte¨ ich mich an dieser Stelle bei allen bedanken, die zum Gelingen dieser Arbeit beigetragen haben. -
Entropy Generation in Mhd Flow of Viscoelastic Nanofluids with Homogeneous-Heterogeneous Reaction, Partial Slip and Nonlinear Thermal Radiation
Journal of Thermal Engineering, Vol. 6, No. 3, pp. 327-345, April, 2020 Yildiz Technical University Press, Istanbul, Turkey ENTROPY GENERATION IN MHD FLOW OF VISCOELASTIC NANOFLUIDS WITH HOMOGENEOUS-HETEROGENEOUS REACTION, PARTIAL SLIP AND NONLINEAR THERMAL RADIATION M. Almakki1, H. Mondal2*, P. Sibanda3 ABSTRACT We investigate the combined effects of homogeneous and heterogeneous reactions in the boundary layer flow of a viscoelastic nanofluid over a stretching sheet with nonlinear thermal radiation. The incompressible fluid is electrically conducting with an applied a transverse magnetic field. The conservation equations are solved using the spectral quasi-linearization method. This analysis is carried out in order to enhance the system performance, with the source of entropy generation and the impact of Bejan number on viscoelastic nanofluid due to a partial slip in homogeneous and heterogeneous reactions flow using the spectral quasi-linearization method. Various fluid parameters of interest such as entropy generation, Bejan number, fluid velocity, shear stress heat and mass transfer rates are studied quantitatively, and their behaviors are depicted graphically. A comparison of the entropy generation due to the heat transfer and the fluid friction is made with the help of the Bejan number. Among the findings reported in this study is that the entropy generation has a significant impact in controlling the rate of heat transfer in the boundary layer region. Keywords: Nanofluids, Viscoelastic Fluid, Homogeneous—Heterogeneous Reactions, Nonlinear Thermal Radiation. INTRODUCTION In recent years, nanofluids have attracted a considerable amount of interest due to their novel properties that make them potentially useful in a number of industrial applications including transportation, power generation, micro manufacturing, thermal therapy for cancer treatment, chemical and metallurgical sectors, heating, cooling, ventilation, and air-conditioning. -
An All-Mach Method for the Simulation of Bubble Dynamics Problems in the Presence of Surface Tension Daniel Fuster, Stéphane Popinet
An all-Mach method for the simulation of bubble dynamics problems in the presence of surface tension Daniel Fuster, Stéphane Popinet To cite this version: Daniel Fuster, Stéphane Popinet. An all-Mach method for the simulation of bubble dynamics problems in the presence of surface tension. Journal of Computational Physics, Elsevier, 2018, 374, pp.752-768. 10.1016/j.jcp.2018.07.055. hal-01845218 HAL Id: hal-01845218 https://hal.sorbonne-universite.fr/hal-01845218 Submitted on 20 Jul 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. An all-Mach method for the simulation of bubble dynamics problems in the presence of surface tension Daniel Fuster, St´ephanePopinet Sorbonne Universit´e,Centre National de la Recherche Scientifique, UMR 7190, Institut Jean Le Rond D'Alembert, F-75005 Paris, France Abstract This paper presents a generalization of an all-Mach formulation for multi- phase flows accounting for surface tension and viscous forces. The proposed numerical method is based on the consistent advection of conservative quan- tities and the advection of the color function used in the Volume of Fluid method avoiding any numerical diffusion of mass, momentum and energy across the interface during the advection step. -
Further Remarks and Comparison with Other Dimensionless Numbers
Do we need the Navier number? – further remarks and comparison with other dimensionless numbers Paweł ZIÓŁKOWSKI∗, Janusz BADUR, Piotr Józef ZIÓŁKOWSKIy Keywords: dimensionless slip-length; external viscosity; internal viscosity; characteristic length; laminar to turbulent transition Abstract: This paper presents the role of the Navier num- ber (Na-dimensionless slip-length) in universal modeling of flow reported in micro- and nano-channels like: capillary biological flows, fuel cell systems, micro-electro-mechanical systems and nano-electro-mechanical systems. Similar to other bulk-like and surface-like dimensionless numbers, the Na number should be treated as a ratio of internal viscous to external viscous momen- tum transport and, therefore, this notion cannot be extended onto whole friction resistance phenomena. Several examples of dimensionless numbers for liquids and rarified gasses flowing in solid channels are presented. Additionally, this article explains the role of the Navier number in predicting closures for laminar to turbulent transition undergoing via eddies detachment from the slip layer in nano-channels. 1. Introduction In capillary biological flows, fuel cell systems (for example SOFC), micro-electro- mechanical systems (MEMS), and nano-electro-mechanical systems (NEMS) it is as- sumed that the external friction between solid and liquid surfaces cannot be further neglected (Beskok and Karniadakis, 1999; Ziółkowski and Zakrzewski, 2013). It in- volves the velocity slip, which is now important not only in the surface momentum transfer, but also in the surface mass, heat transfer, and reactive processes coupled with interfacial transport (Barber and Emerson, 2006). Transport phenomena under- going within a thin shell-like domain require much more complex, surface-like mech- anism of interchanging mass, momentum, and entropy. -
Minimum Size for the Top Jet Drop from a Bursting Bubble
PHYSICAL REVIEW FLUIDS 3, 074001 (2018) Editors’ Suggestion Minimum size for the top jet drop from a bursting bubble C. Frederik Brasz,* Casey T. Bartlett, Peter L. L. Walls, Elena G. Flynn, Yingxian Estella Yu, and James C. Bird† Department of Mechanical Engineering, Boston University, Boston, Massachusetts 02215, USA (Received 14 February 2018; published 11 July 2018) Jet drops ejected from bursting bubbles are ubiquitous, transporting aromatics from sparkling beverages, pathogens from contaminated water sources, and sea salts and organic species from the ocean surface to the atmosphere. In all of these processes, the smallest drops are noteworthy because their slow settling velocities allow them to persist longer and travel further than large drops, provided they escape the viscous sublayer. Yetit is unclear what sets the limit to how small these jet drops can become. Here we directly observe microscale jet drop formation and demonstrate that the smallest jet drops are not produced by the smallest jet drop-producing bubbles, as predicted numerically by Duchemin et al. [Duchemin et al., Phys. Fluids 14, 3000 (2002)]. Through a combination of high-speed imaging and numerical simulation, we show that the minimum jet drop size is set by an interplay of viscous and inertial-capillary forces both prior and subsequent to the jet formation. Based on the observation of self-similar jet growth, the jet drop size is decomposed into a shape factor and a jet growth time to rationalize the nonmonotonic relationship of drop size to bubble size. These findings provide constraints on submicron aerosol production from jet drops in the ocean. -
1 Computational Fluid Dynamics Based Approach for Predicting Heat
Computational Fluid Dynamics Based Approach for Predicting Heat Transfer and Flow Characteristics of Inline Tube Banks with Large Transverse Spacing Niko Pietari Niemelä, Antti Mikkonen, Kaj Lampio, Jukka Konttinen Materials Science and Environmental Engineering, Tampere University, Kalevantie 4, 33100 Tampere, Finland Address correspondence to Niko Pietari Niemelä, Tampere University (TAU), Kalevantie 4, 33100 Tampere, Finland, E-mail: [email protected], Phone Number: +358 40 838 1434 1 ABSTRACT Inline tube configuration is used in various heat exchangers, such as power plant superheaters. The important design parameters are the longitudinal and transverse spacing between the tubes, as they determine the flow and heat transfer characteristics of the tube bank. In superheaters, the transverse tube spacing is often relatively large in order to avoid clogging of the flow passages due to deposition of particulate matter. To design and optimize superheaters is a challenging task, especially because of the complicated vortex-shedding phenomenon. This also complicates the Computational Fluid Dynamics (CFD) modeling, because unsteady simulation approach is required. This paper discusses about various factors that affect the accuracy of prediction of heat transfer and flow characteristics of inline tube banks with large transverse spacing. A suitable CFD model is constructed by comparing different boundary conditions, domain dimensions, domain size, and turbulence models in unsteady simulations. The numerically obtained Nusselt numbers are evaluated against available heat transfer correlations. The correlation of Gnielinski is recommended for tube banks with large transverse spacing, as it agrees within ±13% with the numerically obtained values. The guidelines presented in the paper can serve as reference for future simulations of unsteady flow phenomena. -
Investigation of Air-Cooled Condensers for Waste Heat Driven Absorption Heat Pumps
INVESTIGATION OF AIR-COOLED CONDENSERS FOR WASTE HEAT DRIVEN ABSORPTION HEAT PUMPS A Dissertation Presented to The Academic Faculty by Subhrajit Chakraborty In Partial Fulfillment of the Requirements for the Degree Master of Science in Mechanical Engineering Georgia Institute of Technology May 2017 COPYRIGHT © 2017 BY SUBHRAJIT CHAKRABORTY INVESTIGATION OF AIR-COOLED CONDENSERS FOR WASTE HEAT DRIVEN ABSORPTION HEAT PUMPS Approved by: Dr. Srinivas Garimella, Advisor School of Mechanical Engineering Georgia Institute of Technology Dr. S. Mostafa Ghiaasiaan School of Mechanical Engineering Georgia Institute of Technology Dr. Sheldon M. Jeter School of Mechanical Engineering Georgia Institute of Technology Date Approved: April 25, 2017 To my mother iii ACKNOWLEDGEMENTS I would like to express my deepest gratitude to my advisor, Dr. Srinivas Garimella, for his continuous support and guidance. His direction was invaluable in research- and career-related junctures, and I look forward to applying those skills in future endeavors. I would like to thank past and present members of the Sustainable Thermal Systems Lab, particularly, Dr. Alex Rattner, Dr. Jared Delahanty, David Forinash, Dhruv Hoysall, Marcel Staedter, Dr. Darshan Pahinkar, Anurag Goyal, and Allison Mahvi for their technical guidance, willingness to review my work, and answer my questions. I would specifically like to acknowledge Victor Aiello’s help in fabrication of my components and test facility. In addition, I would like to thank Daniel Kromer, Jennifer Lin, Daniel Boman, Khoudor Keniar, Taylor Kunke, Bachir El Fil and Girish Kini for their scientific counsel and comradery. I am very thankful to my family and friends, without their help and support I would not have been able to complete this work. -
Particle Dynamics in Inertial Microfluidics
PARTICLE DYNAMICS IN INERTIAL MICROFLUIDICS vorgelegt von Master of Science Christian Schaaf ORCID: 0000-0002-4154-5459 an der Fakultät II – Mathematik und Naturwissenschaften der Technischen Universität Berlin zur Erlangung des akademischen Grades Doktor der Naturwissenschaften – Dr. rer. nat. – genehmigte Dissertation Promotionsausschuss: Vorsitzender: Prof. Dr. Michael Lehmann Erster Gutachter: Prof. Dr. Holger Stark Zweiter Gutachter: Prof. Dr. Roland Netz Tag der wissenschaftlichen Aussprache: 17. September 2020 Berlin 2020 Zusammenfassung Die inertiale Mikrofluidik beschäftigt sich mit laminaren Strömungen von Flüssigkeiten durch mikroskopische Kanäle, bei denen die Trägheitseffekte der Flüssigkeit nicht vernach- lässigt werden können. Befinden sich Teilchen in diesen inertialen Strömungen, ordnen sie sich von selbst an bestimmten Positionen auf der Querschnittsfläche an. Da diese Gleich- gewichtspositionen von den Teilcheneigenschaften abhängen, können so beispielsweise Zellen voneinander getrennt werden. In dieser Arbeit beschäftigen wir uns mit der Dynamik mehrerer fester Teilchen, sowie dem Einfluss der Deformierbarkeit auf die Gleichgewichtsposition einer einzelnen Kapsel. Wir verwenden die Lattice-Boltzmann-Methode, um dieses System zu simulieren. Einen wichtigen Grundstein für das Verständnis mehrerer Teilchen bildet die Dynamik von zwei festen Partikeln. Zunächst klassifizieren wir die möglichen Trajektorien, von denen drei zu ungebundenen Zuständen führen und eine über eine gedämpfte Schwingung in einem gebundenem Zustand endet. Zusätzlich untersuchen wir die inertialen Hubkräfte, welche durch das zweite Teilchen stark beeinflusst werden. Dieser Einfluss hängt vor allem vom Abstand der beiden Teilchen entlang der Flussrichtung ab. Im Anschluss an die Dynamik beschäftigen wir uns genauer mit der Stabilität von Paaren und Zügen bestehend aus mehreren festen Teilchen. Wir konzentrieren uns auf Fälle, in denen die Teilchen sich lateral bereits auf ihren Gleichgewichtspositionen befinden, jedoch nicht entlang der Flussrichtung. -
An Exactly Force-Balanced Boundary-Conforming Arbitrary-Lagrangian-Eulerian Method for Interfacial Dynamics
An Exactly Force-Balanced Boundary-Conforming Arbitrary-Lagrangian-Eulerian Method for Interfacial Dynamics Zekang Chenga,b, Jie Lib,a,∗, Ching Y. Lohc, Li-Shi Luoc,d,∗ aDepartment of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ, UK bBP Institute, University of Cambridge, Madingley Road, Cambridge, CB3 0EZ, UK cBeijing Computational Sciences Research Center, Beijing, 100193, China dDepartment of Mathematics & Statistics, Old Dominion University, Norfolk, VA 23529, USA Abstract We present an interface conforming method for simulating two-dimensional and axisymmetric multiphase flows. In the proposed method, the interface is composed of straight segments which are part of mesh and move with the flow. This interface representation is an integral part of an Arbitrary Lagrangian-Eulerian (ALE) method on an moving adaptive unstructured mesh. Our principal aim is to develop an accurate and robust computa- tional method for interfacial flows driven by strong surface tension and with weak viscous dissipation. We first construct discrete solutions satisfying the Laplace law on a circular/spherical interfaces exactly, i.e., the balance between the surface tension and the pressure jump across an interface is achieved exactly. The accuracy and stability of these solutions are then in- vestigated for a wide range of Ohnesorge numbers, Oh. The dimensionless amplitude of the spurious current is reduced to machine zero, i.e., on the order of 10−15 for Oh ≥ 10−3. Finally, the accuracy and capability of the proposed method are demonstrated through a series of benchmark tests with larger interface deformations. In particular, the method is validated with Prosperitti's analytic results of the bubble/drop oscillations and Peregrine's ∗Corresponding author Email addresses: [email protected] (Jie Li), [email protected] (Li-Shi Luo) Preprint submitted to Elsevier January 23, 2020 dripping faucet experiment, in which the values of Oh are small.