Imperial College London
Portrait Picture

Professor Omar K. Matar, FREng

Faculty of Engineering, Department of Chemical Engineering

Head of Department of Chemical Engineering
 
 
 
//

Contact

 

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

 
 
//

Assistant

 

Mr Avery Kitchens +44 (0)20 7594 6263

 
//

Location

 

305 ACEACE ExtensionSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Che:2017:10.1021/acs.langmuir.7b01901,
author = {Che, Z and Matar, OK},
doi = {10.1021/acs.langmuir.7b01901},
journal = {Langmuir},
pages = {12140--12148},
title = {Impact of droplets on liquid films in the presence of surfactant},
url = {http://dx.doi.org/10.1021/acs.langmuir.7b01901},
volume = {33},
year = {2017}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The impact of droplets on liquid films is ubiquitous in natural and industrial processes, and surfactants can significantly alter the impact process by changing the local surface tension. Here we study the impact of droplets on liquid films in the presence of surfactant using high-speed photography, and reveal the flow pattern by dye-tracing. The effects of the droplet size and speed, and the initial film thickness on the impact process are elucidated. The results show that the flow is significantly affected by adding surfactant to the droplet, the liquid film, or to both phases. In particular, the film dye patterns form concentric circles and flower-shaped structures at low and high droplet Weber numbers, respectively. We also show how surfactant-induced Marangoni stresses modify these flow patterns, and alter the characteristics of the phenomena associated with the impact process, such as the propagation of capillary waves, the evolution of the crown, and the formation of secondary droplets. During the impact of surfactant droplets on thin water films, the Marangoni stresses can be sufficiently strong so as to drive film dewetting.
AU  - Che,Z
AU  - Matar,OK
DO  - 10.1021/acs.langmuir.7b01901
EP  - 12148
PY  - 2017///
SN  - 0743-7463
SP  - 12140
TI  - Impact of droplets on liquid films in the presence of surfactant
T2  - Langmuir
UR  - http://dx.doi.org/10.1021/acs.langmuir.7b01901
UR  - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000414383300035&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR  - http://hdl.handle.net/10044/1/56221
VL  - 33
ER  -
Download