Research Fellows Directory
Alfonso Arturo Castrejon-Pita
Dr Alfonso Arturo Castrejon-Pita
University of Oxford
The study of liquid drops and the break-up of jets is important in several natural (physical and biological) and practical (technological) contexts, including defensive and hunting mechanisms of some animals (e.g. velvet worms, bombardier beetles, archerfish), dispersion of liquid drugs into droplets for inhalation, crop- and paint-spraying, the manufacturing of biomaterials, and inkjet printing. It is probably the latter that has gained additional importance, motivated by the advent of printed electronics and 3D printing. On scales of a few micrometres, fluid properties such as viscosity, surface tension, and elasticity are expected to dominate the dynamics of the flow, but the exact dynamics remain unknown, at the very early stages of understanding, or as untested theories. From the scientific point of view, this project aims for a better understanding of the governing laws behind the formation, evolution and break-up of a liquid jet into droplets. On the other hand, alternative methods of producing micro-droplets (especially of high-viscous fluids), and the interaction of the deposited droplets with a wide range of substrates (liquid pools, other drops, powder beds, soft and micromachined materials, etc) is being studied. As the relative importance of the fluid properties changes according to the length (from centimetres to micrometres) and time scales at which the flow is evolving (from minutes to nanoseconds) new experimental, theoretical and numerical techniques to study such challenging conditions have to be developed. The results of these research lines will have a direct impact on several practical applications in which droplets are used to transport material, from new and under-explored applications ranging from electronics, photonics, disease transmission, biotechnology and microchemistry, to the manufacturing of 3D structures by printing methods.
Interests and expertise (Subject groups)