Capillarity and interfacial flows

Work on capillary phenomena in Oxford focusses on topics of interest in applications from industry and other sciences, as well as curiosity-driven research. One particular example of the application of fluid mechanics to other sciences is in the development of microfluidic devices with fluid walls [2,4]. This is intended to change how small fluid volumes are handled in the biosciences and involves collaboration between Ed Walsh (Engineering Science) and Peter Cook (Dunn School of Pathology).

Another body of work focuses on understanding the impact of droplets onto solid surfaces and the resulting splashes. Alfonso Castrejón-Pita and his group have studied the role of surfactants ('soap') in splashing [3] as well as showing that substrate deformability can suppress splashing [1]. The understanding generated by such work is important in applications from inkjet printing to the spread of diseases that are transmitted via water droplets.

[1] C. J. Howland et al., It's harder to splash on soft solids, Phys. Rev. Lett. (2016)

[2] C. Soitu et al., Jet-printing microfluidic devices on demand, Adv. Sci. (2020)

[3] N. Varghese et al., Effect of surfactants on the splashing dynamics of drops impacting smooth substrates, Langmuir (2024).

[4] E. J. Walsh et al., Microfluidics with walls, Nat. Commun. (2017)