Controlling turbulent drag across electrolytes using electric fields

Reversible in operando control of friction is an unsolved challenge that is crucial to industrial tribology. Recent studies show that at low sliding velocities, this control can be achieved by applying an electric field across electrolyte lubricants. However, the phenomenology at high sliding velocities is yet unknown. In this paper, we investigate the hydrodynamic friction across electrolytes under shear beyond the transition to turbulence. We develop a novel, highly parallelised numerical method for solving the coupled Navier–Stokes Poisson–Nernst–Planck equation. Our results show that turbulent drag cannot be controlled across dilute electrolytes using static electric fields alone. The limitations of the Poisson–Nernst–Planck formalism hint at ways in which turbulent drag could be controlled using electric fields.

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Fluid Mixing Control Inside a Y-Shaped Microchannel by Using Electrokinetic Instability

Volume 2: Fora, Parts A and B ◽

10.1115/fedsm2007-37524 ◽

2007 ◽

Cited By ~ 1

Author(s):

Zheyan Jin ◽

Hui Hu

Keyword(s):

Electric Field ◽

Electric Fields ◽

Fluid Mixing ◽

Critical Voltage ◽

Mixing Efficiency ◽

Mixing Process ◽

Static Electric Field ◽

Electrokinetic Instability ◽

Mixing Control ◽

Static Electric Fields

An experimental study was conducted to further our understanding about the fundamental physics of electrokinetic instability (EKI) and to explore the effectiveness to enhance fluid mixing inside a Y-shaped microchannel by manipulating convective EKI waves. The dependence of the critical voltage of applied static electric field to trig EKI to generate convective EKI waves on the conductivity ratio of the two adjacent streams was quantified at first. The effect of the strength of the applied static electric field on the evolution of the convective EKI waves and fluid mixing process were assessed in terms of scalar concentration fields, shedding frequency of the convective EKI waves and scalar mixing efficiency. The effectiveness of manipulating the convective EKI waves by introducing alternative electric perturbations to the applied static electric fields was also explored for the further enhancement of the fluid mixing process inside the Y-shaped microchannel.

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Isothermal crystallization of poly(vinylidene fluoride) in the presence of high static electric fields. II. Effect of crystallization temperature and electric field strength on the crystal phase content and morphology

Journal of Polymer Science Part B Polymer Physics ◽

10.1002/polb.1989.090270510 ◽

1989 ◽

Vol 27 (5) ◽

pp. 1089-1106 ◽

Cited By ~ 27

Author(s):

Hervé Marand ◽

Richard S. Stein

Keyword(s):

Field Strength ◽

Electric Field ◽

Electric Field Strength ◽

Electric Fields ◽

Crystallization Temperature ◽

Isothermal Crystallization ◽

Vinylidene Fluoride ◽

Phase Content ◽

Poly Vinylidene Fluoride ◽

Static Electric Fields

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Electric field assisted alignment of monoatomic carbon chains

Scientific Reports ◽

10.1038/s41598-020-65356-8 ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 1

Author(s):

Stella Kutrovskaya ◽

Igor Chestnov ◽

Anton Osipov ◽

Vlad Samyshkin ◽

Irina Sapegina ◽

...

Keyword(s):

Electric Field ◽

Electric Fields ◽

X Ray Diffraction ◽

Laser Ablation Process ◽

Carbon Chains ◽

High Resolution Tem ◽

The Difference ◽

A Chain ◽

Quasi Crystals ◽

Static Electric Fields

Abstract We stabilize monoatomic carbon chains in water by attaching them to gold nanoparticles (NPs) by means of the laser ablation process. Resulting nanoobjects represent pairs of NPs connected by multiple straight carbon chains of several nanometer lengths. If NPs at the opposite ends of a chain differ in size, the structure acquires a dipole moment due to the difference in work functions of the two NPs. We take advantage of the dipole polarisation of carbon chains for ordering them by the external electric field. We deposit them on a glass substrate by the sputtering method in the presence of static electric fields of magnitudes up to 105 V/m. The formation of one-dimensional carbyne quasi-crystals deposited on a substrate is evidenced by high-resolution TEM and X-ray diffraction measurements. The original kinetic model describing the dynamics of ballistically flowing nano-dipoles reproduces the experimental diagram of orientation of the deposited chains.

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The Effect of Electrostatic Forces on the Distribution of Drops in a Channel

Volume 2: Symposia and General Papers, Parts A and B ◽

10.1115/fedsm2002-31237 ◽

2002 ◽

Author(s):

Arturo Ferna´ndez ◽

Jiacai Lu ◽

Asghar Esmaeeli ◽

Gre´tar Tryggvason

Keyword(s):

Electric Field ◽

Electric Fields ◽

Hydrodynamic Interaction ◽

Stokes Equations ◽

Navier Stokes ◽

Governing Equations ◽

Navier Stokes Equations ◽

Dielectric Fluids ◽

Wide Range ◽

Leaky Dielectric Model

Direct numerical simulations are used to examine the effect of electric fields on the behavior of suspension of drops in dielectric fluids. The effect of electric field is modeled using the “leaky dielectric” model, coupled with the full Navier-Stokes equations. The governing equations are solved using a front-tracking/finite volume technique. The interaction of the drops is strongly dependant on the conductivity and the permittivity ratio, but fibration, where drops line up into long columns, takes place over a wide range of these parameters. The hydrodynamic interaction due to fluid circulation induced by the electric field has a strong influence on the drop distribution and the rate of fibration.

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Insights into ultrafast charge-pair dynamics in P3HT:PCBM devices under the influence of static electric fields

RSC Advances ◽

10.1039/d0ra07935a ◽

2020 ◽

Vol 10 (70) ◽

pp. 42754-42764

Author(s):

Debkumar Rana ◽

Vladislav Jovanov ◽

Veit Wagner ◽

Arnulf Materny ◽

Patrice Donfack

Keyword(s):

Solar Cell ◽

Electric Field ◽

Electric Fields ◽

Electric Field Effects ◽

Field Effects ◽

Static Electric Fields

Electric field effects in P3HT:PCBM solar cell result in polaron-pair-like secondary photoexcitation species showing slower and bimolecular decay characteristics.

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Nonlinear Electrokinetic Transport Under Combined ac and dc Fields in Micro/Nanofluidic Interface Devices

Journal of Fluids Engineering ◽

10.1115/1.4023442 ◽

2013 ◽

Vol 135 (2) ◽

Cited By ~ 7

Author(s):

Vishal V. R. Nandigana ◽

N. R. Aluru

Keyword(s):

Electric Field ◽

Electric Fields ◽

Concentration Polarization ◽

Stokes Equations ◽

Fluid Velocity ◽

Navier Stokes ◽

Electrokinetic Transport ◽

Highly Nonlinear ◽

Interface Devices ◽

Dc Electric Fields

The integration of micro/nanofluidic devices led to many interesting phenomena and one of the most important and complex phenomenon among them is concentration polarization. In this paper, we report new physical insights in micro/nanofluidic interface devices on the application of ac and dc electric fields. By performing detailed numerical simulations based on the coupled Poisson, Nernst–Planck, and incompressible Navier–Stokes equations, we discuss electrokinetic transport and other hydrodynamic effects under the application of combined ac and dc electric fields for different nondimensional electrical double layer (EDL) thicknesses and nanochannel wall surface charge densities. We show that for a highly ion-selective nanochannel, the application of the combined ac/dc electric field, at amplitudes greater than the dc voltage and at a low Strouhal number, results in large dual concentration polarization regions (with unequal lengths) at both the micro/nanofluidic interfaces due to large and unequal voltage drops at these junctions. The highly nonlinear potential distribution gives rise to an electric field and body force that changes the electrokinetic fluid velocity from that obtained on the application of only a dc source.

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Application of electrodynamic drum separator to electronic wastes separation

Gospodarka Surowcami Mineralnymi ◽

10.1515/gospo-2016-0007 ◽

2016 ◽

Vol 32 (1) ◽

pp. 155-174 ◽

Cited By ~ 3

Author(s):

Antoni Cieśla ◽

Wojciech Kraszewski ◽

Mikołaj Skowron ◽

Agnieszka Surowiak ◽

Przemysław Syrek

Keyword(s):

Electric Field ◽

Electric Fields ◽

Electric Field Distribution ◽

Working Space ◽

Dry Conditions ◽

Laboratory Investigations ◽

Rotary Speed ◽

Electrodynamic Separation ◽

Conductive Properties ◽

Static Electric Fields

AbstractStatic electric fields are used, among others, in technological processes such as electric separation. Electrodynamic separation is a process of separating two or more solid phases of various physical properties by electric field forces. The advantage of electrodynamic separation is possibility of obtaining separation of individual components in dry conditions. This eliminates many operations such as thickening, dewatering, hydrotransportation, additional drying which cause higher energy consumption and higher separation process costs. Efficiency of beneficiation depends on many factors such as: electric properties of feed components, feed particle size distribution, drum rotary speed, electric field intensity in working space of separator, configuration of electrodes or surrounding conditions.The paper presents the working of high-voltage drum separator. The analysis of electric field distribution in separator working space was done. Additionally, distribution of forces acting on particles of dielectric and conductive properties was examined, trajectories of charged particles movement were presented too. The laboratory investigations of electronic wastes were performed in two particle fractions: 0.25–0.5 mm and 0–0.25 mm. It was observed that as a result of selective charging of particles they separate according to surface ability to electrifying what allows to obtain selective separation of components being so-called electronic wastes. The application of electrodynamic drum separator allows to separate such elements as Ti, Cu, Fe, Pb, Sn from plastics occurring in electronic wastes.

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MOVEMENT OF CHARGED PARTICLES IN MAGNETIC AND NONUNIFORM STOCHASTIC ELECTRIC FIELDS

10.46813/2021-134-112 ◽

2021 ◽

pp. 112-117

Author(s):

N.A. Azarenkov ◽

A.D. Chibisov ◽

D.V. Chibisov

Keyword(s):

Electric Field ◽

Electric Fields ◽

Cyclotron Frequency ◽

Charged Particles ◽

Planck Equation ◽

Homogeneous Magnetic Field ◽

Equation Of Motion ◽

Stochastic Field ◽

Characteristic Oscillation ◽

Diffusion Motion

The equation of motion of charged plasma particles in a homogeneous magnetic field and in an inhomogeneous stochastic electric field with a characteristic oscillation frequency much lower than the electron cyclotron frequency and much higher than the ion cyclotron frequency is solved. The diffusion motion, as well as the drift of ions and guiding center of electrons, due to the inhomogeneity of the stochastic electric field, is considered. The obtained values of the diffusion coefficient and drift velocity are used in the Fokker-Planck equation to determine the stationary distribution of the plasma density due to the effect of an inhomogeneous stochastic field.

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Tuning the Electric Field Response of MOFs by Rotatable Dipolar Linkers

10.26434/chemrxiv.8153198.v1 ◽

2019 ◽

Author(s):

Johannes P. Dürholt ◽

Babak Farhadi Jahromi ◽

Rochus Schmid

Keyword(s):

Electric Field ◽

Electric Fields ◽

Structural Changes ◽

Dielectric Behavior ◽

Two Dimensions ◽

Dielectric Constants ◽

Electric Response ◽

Dipole Strength ◽

Metal Organic ◽

Dynamics Simulations

Recently the possibility of using electric fields as a further stimulus to trigger structural changes in metal-organic frameworks (MOFs) has been investigated. In general, rotatable groups or other types of mechanical motion can be driven by electric fields. In this study we demonstrate how the electric response of MOFs can be tuned by adding rotatable dipolar linkers, generating a material that exhibits paralectric behavior in two dimensions and dielectric behavior in one dimension. The suitability of four different methods to compute the relative permittivity κ by means of molecular dynamics simulations was validated. The dependency of the permittivity on temperature T and dipole strength μ was determined. It was found that the herein investigated systems exhibit a high degree of tunability and substantially larger dielectric constants as expected for MOFs in general. The temperature dependency of κ obeys the Curie-Weiss law. In addition, the influence of dipolar linkers on the electric field induced breathing behavior was investigated. With increasing dipole moment, lower field strength are required to trigger the contraction. These investigations set the stage for an application of such systems as dielectric sensors, order-disorder ferroelectrics or any scenario where movable dipolar fragments respond to external electric fields.

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