Imperial College London

Professor Omar K. Matar

Faculty of EngineeringDepartment of Chemical Engineering

Vice-Dean (Education), Faculty of Engineering
 
 
 
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Contact

 

+44 (0)20 7594 9618o.matar Website

 
 
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Assistant

 

Miss Nazma Mojid +44 (0)20 7594 3918

 
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Location

 

506ACE ExtensionSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Nowak:2017:10.1039/c7sm00328e,
author = {Nowak, E and Xie, Z and Kovalchuk, NM and Matar, OK and Simmons, MJH},
doi = {10.1039/c7sm00328e},
journal = {Soft Matter},
pages = {4616--4628},
title = {Bulk advection and interfacial flows in the binary coalescence of surfactant-laden and surfactant-free drops},
url = {http://dx.doi.org/10.1039/c7sm00328e},
volume = {13},
year = {2017}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - This work focuses on the study of bulk flows accompanying the coalescence of two aqueous drops, one containing surfactant and the other surfactant-free, in silicone oils of various viscosities. It is observed that the surfactant-free drop intrudes into the surfactant-laden drop in the form of a penetrating jet whose speed increases and average radius decreases with increasing outer phase viscosity. Mixing patterns within the coalescing drops are due to the force imbalance caused by capillary pressure difference and surfactant-induced Marangoni stresses. The driving force for mixing associated with the difference in interfacial tension between the drops is considerably stronger than that related to the drop size. The long timescale mixing of the drops is driven by rapid interior convection, and the subsequent, slow, diffusive process. Three-dimensional numerical simulations show excellent qualitative and quantitative agreement with the experimental results. The implications of our results to formulation strategies of complex microstructures in practical applications are also discussed.
AU - Nowak,E
AU - Xie,Z
AU - Kovalchuk,NM
AU - Matar,OK
AU - Simmons,MJH
DO - 10.1039/c7sm00328e
EP - 4628
PY - 2017///
SN - 1744-683X
SP - 4616
TI - Bulk advection and interfacial flows in the binary coalescence of surfactant-laden and surfactant-free drops
T2 - Soft Matter
UR - http://dx.doi.org/10.1039/c7sm00328e
UR - http://hdl.handle.net/10044/1/52765
VL - 13
ER -