A large amount of the world’s disposable energy is lost through friction and drag. This project will create new types of liquid and liquid-like surfaces which remove liquid friction and drag.
The carnivorous Nepenthes pitcher plant digests insects which slip down a cup-like structure into a trap filled with digestive fluid. The plant has naturally evolved a surface texture to hold a layer of lubricating liquid to create a surface on which insects cannot avoid slipping. In this project, we will take this nature-inspired idea to create new types of surfaces which are solid, but with locked-in films of liquid, or which are solid, but have liquid-like properties, to create new types of super-slippery surfaces.
The project will design, fabricate and test completely new types of lubricated surfaces which allow droplets and liquids to freely move or flow across them. The work will include the lithographic production of textured surfaces, production of porous and granular surfaces, and their treatment to produce lubricated surfaces. Initial experiments will use video observation of how droplets rest and roll or slide across the surfaces. We will consider the physical mechanisms underpinning stick and slip motion, how motion can be controlled and directed, and phase change mechanisms (liquid-vapour and liquid-solid), such as evaporation, condensation and icing. The project will consider how these new surfaces might be used in applications, such as heat exchangers and microfluidics.
Work will be conducted within the School of Engineering of the University and may involve wider collaboration with Universities in the UK and Overseas.
Recent Publications by Supervisor:
- Armstrong, S., McHale, G., Ledesma-Aguilar, R. & Wells, G. G. Pinning-Free Evaporation of Sessile Droplets of Water from Solid Surfaces. Langmuir 35, 2989–2996 (2019).
- McHale, G., Orme, B. V., Wells, G. G. & Ledesma-Aguilar, R. Apparent Contact Angles on Lubricant-Impregnated Surfaces/SLIPS: From Superhydrophobicity to Electrowetting. Langmuir 35, 4197–4204 (2019).
- Guan, J. H. et al. Drop transport and positioning on lubricant-impregnated surfaces. Soft Matter 13, 3404–3410 (2017).
- Guan, J. H. et al. Evaporation of Sessile Droplets on Slippery Liquid-Infused Porous Surfaces (SLIPS). Langmuir 31, 11781–11789 (2015).
Professor Glen McHale
Minimum entry qualification - an Honours degree at 2:1 or above (or International equivalent) in engineering, physics or materials science, possibly supported by an MSc Degree. Further information on English language requirements for EU/Overseas applicants.
Tuition fees + stipend are available for Home/EU students (International students can apply, but the funding only covers the Home/EU fee rate).