Through numerical studies, we examine the dynamics of thin liquid films and drops driven by interfacial stresses arising from surface tension gradients (Marangoni stresses), thermal gradients (thermocapillary stresses) and high frequency vibrational excitation. In the first, we investigate at the effects of the presence of surfactants on drop coalescence, and in their wider context of the phase inversion of liquid-liquid dispersions. In the second, we show through a normal modes analysis and a transient growth analysis that longwave instabilities due to transverse disturbances can lead to the dewetting of thin films and the formation of fractal-like fingering structures, as shown above. In the last, unique phenomena are shown to arise through the highly nonlinear fluid-structural coupling arising from the interaction of high frequency surface vibration with fluids.
In other work, we explore the possibility of synthesizing via novel methods surface nanodroplets and Janus composite liquid marbles.
- LY Yeo, OK Matar, ES Perez de Ortiz, GF Hewitt. Phase Inversion and Associated Phenomena. Multiphase Science & Technology 12, 51 (2000).
- LY Yeo, OK Matar, ES Perez de Ortiz, GF Hewitt. The Dynamics of Marangoni-Driven Local Film Drainage Between Two Drops. J Colloid Interface Sci 241, 233 (2001).
- LY Yeo, OK Matar, ES Perez de Ortiz, GF Hewitt. A Simple Predictive Tool for Modelling Phase Inversion in Liquid-Liquid Dispersions. Chem Eng Sci 57, 1069 (2002).
- LY Yeo, OK Matar, ES Perez de Ortiz, GF Hewitt. Simulation Studies of Phase Inversion in Agitated Vessels Using a Monte Carlo Technique. J Colloid Interface Sci 248, 443 (2002).
- LY Yeo, OK Matar, ES Perez de Ortiz, GF Hewitt. A Description of Phase Inversion Behaviour in Agitated Liquid-Liquid Dispersions Under the Influence of the Marangoni Effect. Chem Eng Sci 57, 3505 (2002).
- LY Yeo, OK Matar, ES Perez de Ortiz, GF Hewitt. Film Drainage Between Two Surfactant Coated Drops Colliding at Constant Approach Velocity. J Colloid Interface Sci 257, 93 (2003).
- LY Yeo, OK Matar. Hydrodynamic Instability of a Thin Viscous Film Between Two Drops. J Colloid Interface Sci 261, 575 (2003).
- LY Yeo, RV Craster, OK Matar. Marangoni Instability of a Thin Liquid Film Resting on a Locally Heated Horizontal Wall. Phys Rev E 67, 056315 (2003).
- A Qi, LY Yeo, JR Friend. Interfacial Destabilization and Atomization Driven by Surface Acoustic Waves. Phys Fluids 20, 074103 (2008).
- MK Tan, JR Friend, LY Yeo. Interfacial Jetting Phenomena Induced by Focused Surface Vibrations. Phys Rev Lett 103, 024501 (2009).
- D Chakraborty, M Bajaj, L Yeo, J Friend, M Pasquali, J Ravi Prakash. Viscoelastic Flow in a Two-Dimensional Collapsible Channel. J Non-Newtonian Fluid Mech 165, 1204-1218 (2010).
- MK Tan, JR Friend, OK Matar, LY Yeo. Capillary Wave Motion Excited by High Frequency Surface Acoustic Waves. Phys Fluids 22, 112112 (2010).
- O Manor, M Dentry, JR Friend, LY Yeo. Substrate Dependent Drop Deformation and Wetting Under High Frequency Vibration. Soft Matter 7, 7976–7979 (2011).
- PK Bhattacharjee, AG McDonnell, R Prabhakar, LY Yeo, J Friend. Extensional Flow of Low-Viscosity Fluids in Capillary Bridges Formed by Pulsed Surface Acoustic Wave Jetting. N J Phys 13, 023005 (2011).
- AR Rezk, O Manor, JR Friend, LY Yeo. Unique Fingering Instabilities and Soliton-Like Wave Propagation in Thin Acoustowetting Films. Nature Commun 3, 1167 (2012).
- O Manor, LY Yeo, JR Friend. The Appearance of Boundary Layers and Drift Flows Due to High-Frequency Surface Waves. J Fluid Mech 707, 482–495 (2012).
- D Chakraborty, J Ravi Prakash, J Friend, L Yeo. Fluid-Structure Interaction in Deformable Microchannels. Phys Fluids 24, 102002 (2012).
- DJ Collins, O Manor, A Winkler, H Schmidt, JR Friend, LY Yeo. Atomization Off Thin Water Films Generated by High Frequency Substrate Wave Vibrations. Phys Rev E 86, 056312 (2012).
- J Blamey, LY Yeo, JR Friend. Microscale Capillary Wave Turbulence Excited by High Frequency Vibration. Langmuir 29, 3835–3845 (2013).
- AR Rezk, O Manor, LY Yeo, JR Friend. Double Flow Reversal in Thin Liquid Films Driven by MegaHertz-Order Surface Vibration. Proc R Soc A 470, 20130765 (2014) [Article coverart selected for journal front cover].
- AG McDonnell, TC Gopesh, J Lo, M O’Bryan, LY Yeo, JR Friend, R Prabhakar. Motility Induced Changes in Viscosity of Suspensions of Swimming Microbes in Extensional Flows. Soft Matter 11, 4658–4668 (2015).
- AG McDonnell, NN Jason, LY Yeo, JR Friend, W Cheng, R Prabhakar. Extensional Viscosity of Copper Nanowire Suspensions in an Aqueous Polymer Solution. Soft Matter 11, 8076–8082 (2015).
- J Wang, L Bao, E Dietrich, RCA van der Veen, S Peng, J Friend, HJW Zandvliet, L Yeo, D Lohse, X Zhang. Mixed Mode of Dissolving Immersed Nanodroplets at a Solid-Water Interface. Soft Matter 11, 1889–1900 (2015) [Article featured in 2015 Soft Matter Hot Papers; coverart selected as journal inner front cover p 1854].
- O Manor, AR Rezk, JR Friend, LY Yeo. Dynamics of Liquid Films Exposed to High-Frequency Surface Vibration. Phys Rev E 91, 053015 (2015).
- L Bao, AR Rezk, LY Yeo, X Zhang. Highly Ordered Arrays of Femtoliter Surface Nanodroplets. Small 11, 4850–4855 (2015).
- JO Castro, BM Neves, AR Rezk, N Eshtiaghi, LY Yeo. Continuous Production of Janus and Composite Liquid Marbles with Tunable Coverage. ACS Appl Mater Interfaces 8, 17751–17756 (2016).
- Z Lu, A Rezk, F Jativa, L Yeo, X Zhang. Dissolution Dynamics of a Suspension Droplet in a Binary Solution for Controlled Nanoparticle Assembly. Nanoscale 9, 13441–13448 (2017) ) [Article coverart selected as journal inner front cover].
- Z Lu, MH Klein Schaarsberg, X Zhu, LY Yeo, D Lohse, X Zhang. Universal Nanodroplet Branches from Confining the Ouzo Effect. Proc Natl Acad Sci USA 114, 10332–10337 (2017).
- JO Castro, SR Ramesan, AR Rezk, LY Yeo. Continuous Tuneable Droplet Ejection via Pulsed Surface Acoustic Wave Jetting. Soft Matter 14, 5721–5727 (2018) Article coverart selected as journal front cover; Correction: pp 5937–5938].
- S Das, MI Mohammed, I Gibson, L Weerasiri, A McDonnell, J Xiang, L Yeo. Oscillation Characteristics of Low Weber Number Impinging Micro-Droplets. Theor Comput Fluid Dyn 33, 197–213 (2019).
- JO Castro, SR Ramesan, HD Dang, AR Rezk, LY Yeo. Acoustopipetting: Tuneable Nanoliter Sample Dispensing Using Surface Acoustic Waves. Anal Chem 91, 5621–5628 (2019).
- A McDonnell, J-h Lee, E Makrai, LY Yeo, LE Downie. Tear Film Extensional Viscosity is a Novel Potential Biomarker of Dry Eye Disease. Ophthamology 126, 1196–1198 (2019).