Drop splashing after impact onto immiscible pools of different viscosities

<p>Droplet impact&nbsp;onto liquid pools is a canonical scenario relevant to numerous natural phenomena and industrial processes. However, despite their ubiquity,&nbsp;multi-fluid systems&nbsp;with the drop and pool consisting of&nbsp;different liquids&nbsp;are far less wel...

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Главные авторы: Fudge, BD, Cimpeanu, R, Antkowiak, A, Castrejón-Pita, AA, Castrejón-Pita, JR
Формат: Journal article
Язык:English
Опубликовано: Elsevier 2023
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author Fudge, BD
Cimpeanu, R
Antkowiak, A
Castrejón-Pita, AA
Castrejón-Pita, JR
author_facet Fudge, BD
Cimpeanu, R
Antkowiak, A
Castrejón-Pita, AA
Castrejón-Pita, JR
author_sort Fudge, BD
collection OXFORD
description <p>Droplet impact&nbsp;onto liquid pools is a canonical scenario relevant to numerous natural phenomena and industrial processes. However, despite their ubiquity,&nbsp;multi-fluid systems&nbsp;with the drop and pool consisting of&nbsp;different liquids&nbsp;are far less well understood. Our&nbsp;hypothesis&nbsp;is that the post-impact dynamics greatly depends on the&nbsp;pool-to-droplet viscosity ratio&nbsp;<em>&mu;<sub>p</sub>/&mu;<sub>d</sub></em>, which we explore over a range of six orders of magnitude using a combination of&nbsp;experiments&nbsp;and&nbsp;theoretical approaches&nbsp;(mathematical modelling and direct numerical simulation). Our&nbsp;findings&nbsp;indicate that in this scenario the&nbsp;splashing threshold&nbsp;and the&nbsp;composition&nbsp;of the&nbsp;ejecta&nbsp;sheet&nbsp;are controlled by the viscosity ratio. We uncover that increasing the pool viscosity decreases the splashing threshold for high viscosity pools (<em>&mu;<sub>p</sub>/&mu;<sub>d</sub></em>≳35) when the splash comes from the droplet. By contrast, for low viscosity pools, the splash sheet comes from the pool and increasing the pool viscosity increases the splashing threshold. Surprisingly, there are conditions for which no splashing is observed under the conditions attainable in our laboratory. Furthermore, considering the interface velocity together with asymptotic arguments underlying the generation of the ejecta has allowed us to understand meaningful variations in the pressure during impact and rationalise the observed changes in the splashing threshold.</p>
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spelling oxford-uuid:63616568-82e0-496c-9659-3aefc7defba92023-07-07T06:53:50ZDrop splashing after impact onto immiscible pools of different viscositiesJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:63616568-82e0-496c-9659-3aefc7defba9EnglishSymplectic ElementsElsevier2023Fudge, BDCimpeanu, RAntkowiak, ACastrejón-Pita, AACastrejón-Pita, JR<p>Droplet impact&nbsp;onto liquid pools is a canonical scenario relevant to numerous natural phenomena and industrial processes. However, despite their ubiquity,&nbsp;multi-fluid systems&nbsp;with the drop and pool consisting of&nbsp;different liquids&nbsp;are far less well understood. Our&nbsp;hypothesis&nbsp;is that the post-impact dynamics greatly depends on the&nbsp;pool-to-droplet viscosity ratio&nbsp;<em>&mu;<sub>p</sub>/&mu;<sub>d</sub></em>, which we explore over a range of six orders of magnitude using a combination of&nbsp;experiments&nbsp;and&nbsp;theoretical approaches&nbsp;(mathematical modelling and direct numerical simulation). Our&nbsp;findings&nbsp;indicate that in this scenario the&nbsp;splashing threshold&nbsp;and the&nbsp;composition&nbsp;of the&nbsp;ejecta&nbsp;sheet&nbsp;are controlled by the viscosity ratio. We uncover that increasing the pool viscosity decreases the splashing threshold for high viscosity pools (<em>&mu;<sub>p</sub>/&mu;<sub>d</sub></em>≳35) when the splash comes from the droplet. By contrast, for low viscosity pools, the splash sheet comes from the pool and increasing the pool viscosity increases the splashing threshold. Surprisingly, there are conditions for which no splashing is observed under the conditions attainable in our laboratory. Furthermore, considering the interface velocity together with asymptotic arguments underlying the generation of the ejecta has allowed us to understand meaningful variations in the pressure during impact and rationalise the observed changes in the splashing threshold.</p>
spellingShingle Fudge, BD
Cimpeanu, R
Antkowiak, A
Castrejón-Pita, AA
Castrejón-Pita, JR
Drop splashing after impact onto immiscible pools of different viscosities
title Drop splashing after impact onto immiscible pools of different viscosities
title_full Drop splashing after impact onto immiscible pools of different viscosities
title_fullStr Drop splashing after impact onto immiscible pools of different viscosities
title_full_unstemmed Drop splashing after impact onto immiscible pools of different viscosities
title_short Drop splashing after impact onto immiscible pools of different viscosities
title_sort drop splashing after impact onto immiscible pools of different viscosities
work_keys_str_mv AT fudgebd dropsplashingafterimpactontoimmisciblepoolsofdifferentviscosities
AT cimpeanur dropsplashingafterimpactontoimmisciblepoolsofdifferentviscosities
AT antkowiaka dropsplashingafterimpactontoimmisciblepoolsofdifferentviscosities
AT castrejonpitaaa dropsplashingafterimpactontoimmisciblepoolsofdifferentviscosities
AT castrejonpitajr dropsplashingafterimpactontoimmisciblepoolsofdifferentviscosities