Surfactant effect on bubble deformation and breakup after interaction with vortex structure

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985858%3A_____%2F24%3A00598143" target="_blank" >RIV/67985858:_____/24:00598143 - isvavai.cz</a>

Výsledek na webu

<a href="https://hdl.handle.net/11104/0355873" target="_blank" >https://hdl.handle.net/11104/0355873</a>

DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Surfactant effect on bubble deformation and breakup after interaction with vortex structure

Popis výsledku v původním jazyce

Bubble – vortex interaction is studied experimentally in order to find out the effect of surfactants on bubble deformation and possible breakup. Experiments are based on visualization of a single bubble interacting with a single vortex-ring generated in liquid. Design of the experiment enables to control both the vortex-ring energy and the bubble size. A high-speed camera is used to record the whole interaction process: the initial free rise of mother bubble, then the interaction of mother bubble with vortex-ring, bubble deformations, possible breakup and size distribution of all daughter bubbles generated by breakup. The effect of surfactant is investigated using α-terpineol as model surfactant, in two concentrations 1⸱10-3 and 3⸱10-3 mol/L. The presence of surfactant causes the suppression of the bubble deformation and more energy is required to sufficiently deform the bubble and its breakage. Therefore, the interaction process results in bubble breakup less frequently. The static surface tension is found to be insufficient to characterise the bubble surface energy, a new scaling of the bubble breakup process is proposed. The dimensionless damping time of bubble shape oscillations is used as a parameter to scale the breakup time necessary bubble to sufficiently deform and break. This damping time is a measure of energy dissipation at the bubble interface during the shape oscillations and its magnitude differs in pure liquids and in surfactant solutions.

Název v anglickém jazyce

Surfactant effect on bubble deformation and breakup after interaction with vortex structure

Popis výsledku anglicky

Bubble – vortex interaction is studied experimentally in order to find out the effect of surfactants on bubble deformation and possible breakup. Experiments are based on visualization of a single bubble interacting with a single vortex-ring generated in liquid. Design of the experiment enables to control both the vortex-ring energy and the bubble size. A high-speed camera is used to record the whole interaction process: the initial free rise of mother bubble, then the interaction of mother bubble with vortex-ring, bubble deformations, possible breakup and size distribution of all daughter bubbles generated by breakup. The effect of surfactant is investigated using α-terpineol as model surfactant, in two concentrations 1⸱10-3 and 3⸱10-3 mol/L. The presence of surfactant causes the suppression of the bubble deformation and more energy is required to sufficiently deform the bubble and its breakage. Therefore, the interaction process results in bubble breakup less frequently. The static surface tension is found to be insufficient to characterise the bubble surface energy, a new scaling of the bubble breakup process is proposed. The dimensionless damping time of bubble shape oscillations is used as a parameter to scale the breakup time necessary bubble to sufficiently deform and break. This damping time is a measure of energy dissipation at the bubble interface during the shape oscillations and its magnitude differs in pure liquids and in surfactant solutions.

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

<a href="/cs/project/GA22-29605S" target="_blank" >GA22-29605S: Interakce bubliny nebo kapky s toroidním vírem</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2024

Kód důvěrnosti údajů

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