Computational fluid dynamics model of rhythmic motion of charged droplets between parallel electrodes

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F17%3A43913822" target="_blank" >RIV/60461373:22340/17:43913822 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.cambridge.org/core/journals/journal-of-fluid-mechanics/article/computational-fluid-dynamics-model-of-rhythmic-motion-of-charged-droplets-between-parallel-electrodes/453956C175E955F82510EEC1010B820E" target="_blank" >https://www.cambridge.org/core/journals/journal-of-fluid-mechanics/article/computational-fluid-dynamics-model-of-rhythmic-motion-of-charged-droplets-between-parallel-electrodes/453956C175E955F82510EEC1010B820E</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1017/jfm.2017.230" target="_blank" >10.1017/jfm.2017.230</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Computational fluid dynamics model of rhythmic motion of charged droplets between parallel electrodes

Popis výsledku v původním jazyce

A mathematical electrodes is developed in this study. The work is motivated by recent experimental findings that report oscillatory behaviour of water in oil droplets under a direct current electric field. The model considers the presence of a charged droplet placed in a dielectric medium. The droplet is immediately attracted to the electrode with the opposite polarity. When approaching the electrode, the electric charge is electrochemically reversed within the droplet, which is then repelled to the other electrode. The entire process can periodically repeat. The model is able to track a deformable liquid-liquid interface, the dynamics of the wetting process at the electrodes and the dynamics of electrochemical charge transfer between the droplet and the electrodes. The dependences of the oscillation frequency, charge acquired by the droplet and charging time on several model parameters (surface charge density on electrodes, kinetic parameter of charging, droplet-electrode contact angle, droplet size, liquid permittivity) are examined. Qualitative agreement of the model predictions with available experimental data is obtained, e.g. the oscillation frequency increases with growing electric field strength or droplet size. Our model represents the first successful attempt to predict oscillatory motion of aqueous droplets by a pseudo-three-dimensional two-phase approach. Our model also strongly supports the theory that the oscillatory motion relies on the combination of electrochemical charge injection at the electrodes and electrostatic attraction/repulsion processes.

Název v anglickém jazyce

Computational fluid dynamics model of rhythmic motion of charged droplets between parallel electrodes

Popis výsledku anglicky

A mathematical electrodes is developed in this study. The work is motivated by recent experimental findings that report oscillatory behaviour of water in oil droplets under a direct current electric field. The model considers the presence of a charged droplet placed in a dielectric medium. The droplet is immediately attracted to the electrode with the opposite polarity. When approaching the electrode, the electric charge is electrochemically reversed within the droplet, which is then repelled to the other electrode. The entire process can periodically repeat. The model is able to track a deformable liquid-liquid interface, the dynamics of the wetting process at the electrodes and the dynamics of electrochemical charge transfer between the droplet and the electrodes. The dependences of the oscillation frequency, charge acquired by the droplet and charging time on several model parameters (surface charge density on electrodes, kinetic parameter of charging, droplet-electrode contact angle, droplet size, liquid permittivity) are examined. Qualitative agreement of the model predictions with available experimental data is obtained, e.g. the oscillation frequency increases with growing electric field strength or droplet size. Our model represents the first successful attempt to predict oscillatory motion of aqueous droplets by a pseudo-three-dimensional two-phase approach. Our model also strongly supports the theory that the oscillatory motion relies on the combination of electrochemical charge injection at the electrodes and electrostatic attraction/repulsion processes.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20402 - Chemical process engineering

Projekt

<a href="/cs/project/GA14-01781S" target="_blank" >GA14-01781S: Výzkum mechaniky tekutin v inteligentních mikrosystémech řízených elektrickými poli</a><br>

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Fluid Mechanics

ISSN

0022-1120

e-ISSN

—

Svazek periodika

822

Číslo periodika v rámci svazku

7

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

23

Strana od-do

31-53

Kód UT WoS článku

000403090300008

EID výsledku v databázi Scopus

2-s2.0-85020278225