Imperial College London

Professor Omar K. Matar

Faculty of EngineeringDepartment of Chemical Engineering

Vice-Dean (Education), Faculty of Engineering



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




Miss Nazma Mojid +44 (0)20 7594 3918




506ACE ExtensionSouth Kensington Campus






BibTex format

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 = {},
volume = {33},
year = {2017}

RIS format (EndNote, RefMan)

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 -
UR -
UR -
VL - 33
ER -