When a liquid comes into contact with a solid surface, its interface can be pinned by surface texture, giving rise to the ubiquitous phenomenon of the contact angle hysteresis . Inspired by the Nepenthes pitcher plant, SLIPS (Slippery Liquid-Infused Porous Surfaces) have been recently introduced to enhance the liquid mobility by reducing the contact to the solid surface, and therefore the driving force required for liquid manipulation . The growing interest in SLIPS, lead to applications in areas such as food packaging and biomedical devices, which involve fluids with complex (non-Newtonian) rheological properties. Despite that, to date most studies of SLIPS address mainly equilibrium properties or dynamics of simple (Newtonian) liquids. In contrast, it is expected that the combination of solid texture, shape of liquid interfaces and complex fluid rheology will play a dominant role in liquid motion. This PhD project aims at exploring with experiments the impact of non-Newtonian liquid rheology on the Physics of SLIPS, where both the lubricant and the flowing liquid can be complex. The experimental investigation will be complemented by numerical simulations performed in the group  and to which the student will also contribute. After gaining insight on the fundamental mechanisms determining the flow properties, in collaboration with the project partners, the student will develop and test new surface designs exploiting the complex flow properties to control the liquid transport on non Newtonian SLIPS.
The Principal Supervisor for this project is Dr Ciro Semprebon.
Please note eligibility requirement:
• Academic excellence of the proposed student i.e. 2:1 (or equivalent GPA from non-UK universities [preference for 1st class honours]) in Physics or Engineering; or a Masters (preference for Merit or above); or APEL evidence of substantial practitioner achievement.
• Appropriate IELTS score, if required.
• Applicants cannot apply for this funding if currently engaged in Doctoral study at Northumbria or elsewhere.
This project is well suited to motivated and hard-working candidates with a keen interest in wetting and fluid dynamic properties in smart materials. The applicant should have excellent communication skills including proven ability to write in English.
For more information and informal enquiries please contact Dr. Ciro Semprebon, +44 (0)191 227 3045.
For further details of how to apply, entry requirements and the application form, see https://www.northumbria.ac.uk/research/postgraduate-research-degrees/how-to-apply/
Please note: Applications that do not include a research proposal of approximately 1,000 words (not a copy of the advert), or that do not include the advert reference (e.g. FAC19/EE/MPEE/SEMPREBON) will not be considered.
Start Date: 1 March 2020
Northumbria University takes pride in, and values, the quality and diversity of our staff. We welcome applications from all members of the community. The University holds an Athena SWAN Bronze award in recognition of our commitment to improving employment practices for the advancement of gender equality and is a member of the Euraxess network, which delivers information and support to professional researchers.
 “Apparent contact angle and contact angle hysteresis on liquid infused surfaces”, C. Semprebon, G.McHale, H. Kusumaatmaja. Soft Matter, 2016 DOI: 10.1039/c6sm00920d.
 “Droplet Retention and Shedding on Slippery Substrates”, B. Orme, G. McHale, R. Ledesma-Aguilar, and G. Wells. Langmuir 2019, 35, 9146−9151
 “Drop Dynamics on Liquid-Infused Surfaces: The Role of the Lubricant Ridge”, M. S. Sadullah, C. Semprebon and H. Kusumaatmaja, Langmuir 2018, 34, 8112−8118