My research is on flows of dry granular materials, and in particular on gravity currents, where the flow is driven by gravity and resisted by friction. In some ways granular gravity currents are similar to those with water, as in a river or canal: for example, they can form hydraulic jumps and drops, and waves can form on their surface. I am particularly interested in the link between microscopic (grain-level) properties and macroscopic flow properties, such as friction or velocity profiles.
I use a combination of mathematical modelling and discrete particle simulations (see below).
I presented a poster at the Gordon Research Conference on Granular Matter in July 2016. (A higher-resolution version is available here.) I also made a poster that displays some of the work by other people in the granular group.
- Topographical effects on granular gravity currents, given to the UK Fluids Network’s Special Interest Group on granular flows, on Friday 31 March 2017, at Cambridge.
- Topographical effects on granular gravity currents, identically titled but substantially different, given at the APS DFD meeting on Sunday 20 November 2016, in Portland, OR.
- Not-so-continuum mechanics, given to the London Mathematical Society on 11 November 2016
Discrete particle method (DPM) simulations are a class of methods for studying granular materials or suspensions. In a DPM simulation, one calculates the motions of and interactions between individual particles; one specifies ‘microscopic’ contact laws between particles to determine the forces, and then time-evolve the system according to Newton’s second law. The advantage of DPM over practical experiments is that the former is often much cheaper, and gives us information that would be difficult to measure in reality. Unfortunately, real granular systems contain millions of grains and it would be impractical to simulate all of them; DPM simulations therefore need one to choose sensible approximations, as well as many algorithmic tricks.
We use the package MercuryDPM, which is developed by MercuryLab, based at the University of Twente. In May 2017, I became a developer for MercuryDPM.
When I was an undergraduate, I was interested in mathematical biology (thanks in part to the influence of Julia Gog). I did two summer projects: one with Julia and Michael Leader on genome packaging in influenza, and one at the Sainsbury Laboratory.