So it's been three months since I arrived in the UK and started my work at Warwick. The first week or so was spent choosing the first project to work on. While the grant I am paid from is, formally at least, for studying drop impact on a solid surface, it makes sense, especially for a newbie like myself, to start with something simpler that still includes the same ingredients: a free-surface liquid flow, a non-equilibrium gas flow and their interactions. So after a few discussions with James and Duncan, I decided to start with collisions between drops, still a remarkably rich problem with some open questions. Next I had to choose a computational tool to use. As always, you can write your own code, which gives you maximum flexibility but takes time. Or you can use something written by others, which gives you an easy start, but you may well encounter serious obstacles later on. As I was eager to start quickly, I decided that I would rather try the latter possibility and settled on FreeFem++, finite element software written by F. Hecht from Paris. It has a built-in mesh generator with the possibility of anisotropic mesh adaptation, several linear algebra solvers, and you just need to specify your PDE in the weak form — FreeFem++ generates the corresponding set of finite-element equations, solves it and produces graphical output for you. So a simple problem like droplet oscillation takes just a dozen lines or so in the built-in scripting language. Of course, once you do something more complicated, it becomes increasingly hard to use, so, unsurprisingly, by now my code is much longer than that and I am likely to decide to switch to something else eventually. But I don't regret starting with FreeFem++ — it has been a good learning experience.
Being a novice, I also need to learn more about my research area. So I appreciated the opportunity to attend a workshop on drop impact at Imperial College where James gave a talk. There was a nice variety of talks (experimental, theoretical and computational) on both the basic drop impact problem and its complications (e.g., impact on soft, porous and moving surfaces), as well as other related problems (water entry by a solid, dynamic wetting, drop evaporation). It was interesting to meet Jie Li from Cambridge who has recently developed a computational model of drop collision — hopefully, we will be able to improve and extend his study.
There have been some learning opportunities at Warwick as well. I particularly appreciate the number of interesting seminars here — I usually attend three or four a week, sometimes more, in maths, physics and engineering. We have also started weekly group meetings. I am formally in charge, although this does not involve much more than sending reminders to everybody a couple of days in advance. Many new people have joined the group recently and so the goal for this term is to get to know each other. With this in mind we take turns giving informal talks (sometimes very informal!) about our past experiences and current projects. The discussions are lively and a great way to learn, exercise our brains and have fun.
It's not all just work here, of course. Our trip to Wales has already been described in this blog by Dave. As for me personally, I have been able to indulge in my favourite pastime of orienteering, taking part in races in the streets and alleys of Oxford and the town of Warwick, sand dunes of Anglesey and Cumbria, and a Lake District fell.