La Electrohidrodinámica es una rama de la electrodinámica de medios continuos que estudia el movimiento de fluidos dieléctricos bajo la aplicación de campos eléctricos. Estos fluidos presentan una conductividad pequeña, por lo que las corrientes que los atraviesan son siempre muy débiles, y, por tanto, el campo magnético inducido por estas...
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June 1, 2018 (v1)PublicationUploaded on: March 27, 2023
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August 1, 2018 (v1)Publication
Injection of charge by a sharp electrode into a surrounding dielectric liquid leads to Coulomb forces that set the liquid into motion. An analysis is presented of this motion in a small region around the edge of the electrode, which determines the injected current as a function of the far electric potential seen by this region. By using an...
Uploaded on: March 27, 2023 -
June 27, 2018 (v1)Publication
The aim of this paper is to explore the capability of Discontinuous Galerkin Finite Element methods to solve numerically the charge transport equation in EHD convective flows, in both strong and weak injection regimes. These methods are especially suited to treat purely hyperbolic problems, as it is the charge transport equation in most EHD...
Uploaded on: March 27, 2023 -
July 27, 2018 (v1)Publication
This paper presents a self-consistent model of electrohydrodynamic (EHD) laminar plumes produced by electron injection from ultra-sharp needle tips in cyclohexane. Since the density of electrons injected into the liquid is well described by the Fowler-Nordheim field emission theory, the injection law is not assumed. Furthermore, the generation...
Uploaded on: December 4, 2022 -
July 27, 2018 (v1)Publication
A dielectric fluid can be set into motion with the help of electric forces, mainly Coulomb force. This phenomenon, called electroconvection, can be induced by electrohydrodynamic conduction, injection, and induction. Conduction is based on the dissociation/recombination phenomenon, generates heterocharge layers, and occurs for low electric...
Uploaded on: December 4, 2022 -
June 26, 2018 (v1)Publication
This paper deals with self similar thermal and electrohydrodynamic (EHD) plumes. The former arises from hot lines or points, whereas the latter arises when sharp metallic contours submerged in non conducting liquids support high electrostatic potential, resulting in charge injection. Although the motive force is buoyancy in one case and Coulomb...
Uploaded on: March 27, 2023 -
June 26, 2018 (v1)Publication
The time evolution of the problem of Electrohydrodynamic (EHD) convection in a liquid between two plates is analysed numerically. The equations are nondimensionalized using the ion drift velocity and the viscous time scales. Following the non-dimensionalisation of the respective model, two different techniques have been used to describe the...
Uploaded on: March 27, 2023 -
December 20, 2018 (v1)Publication
A rigorous and complete formulation of the linear evolution of harmonically stimulated capillary jets should include infinitely many spatial modes to account for arbitrary exit conditions [J. Guerrero et al., J. Fluid Mech. 702, 354 (2012)]. However, it is not rare to find works in which only the downstream capillary dominant mode, the sole...
Uploaded on: December 4, 2022 -
July 10, 2018 (v1)Publication
We numerically investigated the annular electroconvection that takes place in a dielectric liquid lying between two concentric cylinder electrodes. A uniform injection of arbitrary strengths either from the inner or outer cylinder introduces free charge carriers into the system, and the resulting Coulomb force induces electroconvection. The...
Uploaded on: March 27, 2023 -
July 11, 2018 (v1)Publication
The hydrodynamic stability of a dielectric liquid subjected to strong unipolar injection is numerically investigated. We determined the linear criterion Tc (T being the electric Rayleigh number) and finite amplitude one Tf over a wide range of the mobility parameter M. A noticeable discrepancy is shown for Tf between our numerical prediction...
Uploaded on: December 4, 2022 -
July 3, 2018 (v1)Publication
This work addresses the stability of a two-dimensional plane layer of a dielectric liquid enclosed in wall bounded cavities of different aspect ratios and subjected to unipolar injection of ions. Numerical simulations have been conducted to investigate the effect of lateralwalls, especially in the development of the...
Uploaded on: March 27, 2023 -
July 31, 2018 (v1)Publication
We study the linear stability and nonlinear behavior of the electroconvection between two concentric halfcylinders with no-slip conditions on all boundaries. The no-slip condition makes impossible to apply the standard modal approach. Hence, we apply a finite element technique similar to the one we have used in a previous paper about the...
Uploaded on: December 4, 2022 -
July 4, 2018 (v1)Publication
We perform a theoretical and numerical study of the Coulomb-driven electroconvection flow of a dielectric liquid between two coaxial cylinders. The specific case where the inner to outer diameter ratio is 0.5 is analyzed. A strong unipolar injection of ions either from the inner or outer cylinder is considered to introduce free charger carriers...
Uploaded on: March 27, 2023 -
July 4, 2018 (v1)Publication
We investigate the linear stability threshold of a dielectric liquid subjected to unipolar injection in a 2D rectangular enclosure with rigid boundaries. A finite element formulation transforms the set of linear partial differential equations that governs the system into a set of algebraic equations. The resulting system poses an eigenvalue...
Uploaded on: March 27, 2023 -
June 25, 2018 (v1)Publication
In this paper electrohydrodynamic (EHD) plumes are examined in the region far from the injecting electrode and the collector plate, for both two-dimensional and axisymmetric geometries. The relative importance of the conduction mechanisms (convection, drift and diffusion of electric charge) is analyzed. Diffusion turns out to be negligible...
Uploaded on: March 27, 2023 -
November 18, 2019 (v1)Publication
In this work, we discuss the fundamental aspects of Electrohydrodynamic (EHD) conduction pumping of dielectric liquids. We build a mathematical model of conduction pumping that can be applied to all sizes, down to microsized pumps. In order to do this, we discuss the relevance of the Electrical Double Layer (EDL) that appears naturally on...
Uploaded on: March 27, 2023