Flow‐induced coalescence involving attractive interparticle forces

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389013%3A_____%2F19%3A00504714" target="_blank" >RIV/61389013:_____/19:00504714 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Flow‐induced coalescence involving attractive interparticle forces

Popis výsledku v původním jazyce

Coalescence is one of mechanisms of increasing average size of droplets dispersed in a matrix. Extensional‐flow‐induced coalescence where the motion can be described using two coordinates, distance and angle, and shear‐flow‐coalescence described in three dimensions have been studied. Unlike approaches in most of our previous papers where trajectories are solved as dependence of distance on angle or of distance and polar angle on azimuth, parallel integration of all spatial coordinates with respect to time is employed here, which allowed also more correct solution of coalescence including attractive forces. In contrast to previous studies, where interdroplet interaction is neglected till their close approach, this paper is based on the switch between equations describing hydrodynamic interactions between droplets at their moderate distance and equations for matrix drainage between close droplets. The results have been compared for zero and finite critical distance with and without considering van der Waals forces. For droplets keeping spherical shape during coalescence, non‐zero critical distance plays qualitatively the same role as attractive forces in calculation of collision. On the other hand, the critical distance cannot be omitted in models considering droplets flattening where the motion equations diverge for zero intersurface distance.

Název v anglickém jazyce

Flow‐induced coalescence involving attractive interparticle forces

Popis výsledku anglicky

Coalescence is one of mechanisms of increasing average size of droplets dispersed in a matrix. Extensional‐flow‐induced coalescence where the motion can be described using two coordinates, distance and angle, and shear‐flow‐coalescence described in three dimensions have been studied. Unlike approaches in most of our previous papers where trajectories are solved as dependence of distance on angle or of distance and polar angle on azimuth, parallel integration of all spatial coordinates with respect to time is employed here, which allowed also more correct solution of coalescence including attractive forces. In contrast to previous studies, where interdroplet interaction is neglected till their close approach, this paper is based on the switch between equations describing hydrodynamic interactions between droplets at their moderate distance and equations for matrix drainage between close droplets. The results have been compared for zero and finite critical distance with and without considering van der Waals forces. For droplets keeping spherical shape during coalescence, non‐zero critical distance plays qualitatively the same role as attractive forces in calculation of collision. On the other hand, the critical distance cannot be omitted in models considering droplets flattening where the motion equations diverge for zero intersurface distance.

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

10404 - Polymer science

Projekt

<a href="/cs/project/GA14-17921S" target="_blank" >GA14-17921S: Vícefázové biodegradabilní polymerní systémy</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

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