PhD Title: Computational Modelling of Leidenfrost Fractals
PhD Supervisors: James Sprittles and Duncan Lockerby
My undergraduate degree was at Mansfield College, University of Oxford. I initially studied Mathematics, specialising in fluid dynamics, numerical methods and mathematical physics. At the end of my third year I undertook a summer research project investigating large-scale structures in turbulent fluids. I then switched to Mathematical and Theoretical Physics for my Masters year, graduating with a first class MMathPhys degree. My masters thesis used self-consistent field theory to model polymer melts.
My PhD research investigates the behaviour of the thin gas layer formed when a liquid droplet impacts onto a solid surface. In particular I am interested in Leidenfrost conditions, when the solid is significantly hotter than the boiling point of the liquid droplet, causing a layer of the liquid's vapour to form between the drop and the solid. Fractal-like contact patterns have been observed in the motion of the line where the liquid makes contact with the solid, as well as a rich variety of behaviour during the contact or rebound of the drop, with the vapour layer cushioning the impact. This problem contains physics beyond those captured by the classic Navier-Stokes equations of fluid dynamics, including moving contact lines and kinetic effects in the gas film.
I am working on developing and testing a numerical model to predict when and how contact occurs during the impact of a drop in Leidenfrost conditions. This modelling involves multi-scale numerical simulations using the finite element method. Currently, I am focused on the impacts of droplets onto smooth surfaces in isothermal conditions, and on head-on collisions between identical droplets, and when drops will merge or bounce in these conditions. I am working on comparing to experimental data with the aim of predicting the critical impact speed at which drops will merge.