Can you tell us a bit about yourself?
“I had almost not gone into fusion research at all! When I started my PhD work at Zhejiang University in China, I was part of a group that studied both space and laboratory plasmas — interplanetary and tokamak physics. I was originally going to study magnetic reconnection between the plasma in the solar wind and Earth’s magnetosphere, but our group decided to fully focus on fusion, which turned out to be equally interesting. I enjoyed working on advanced computational models for the complex behaviour of plasmas in fusion devices. That is also the topic of my post-doctoral work at the German IPP institute.”
What is your ERG project about?
“A big question about fusion is how we can get the plasma in future tokamak power plants to behave nicely. We know of a process called the sawtooth instability, which is caused by central heating and current drive. Sawteeth (named after the shape they make on a graph) can destroy the magnetic surfaces and even terminate the plasma discharge in so-called disruptions if they go unchecked. The usual ways to control sawteeth include carefully injecting heating beams and inducing electrical current at the desired deposition locations. But that can lead to other stability issues and technical challenges.”
“What we really want is for the plasma to tame itself. The technical term is getting it into a state called a flux pumping scenario, where the magnetic fields and plasma flows self-organise to keep the plasma helically stable by redistributing plasma current and pressure. One challenge is that different smaller tokamaks reach flux pumping under significantly different conditions. We hope to extend and use the JOREK computational code to get a unified model of the underlying physics. Then we can predict how to reach flux pumping in larger future machines like ITER and DEMO.”
How did you end up applying for an ERG grant?
“I was already working on this topic in my post-doc at IPP when my supervisor suggested the ERG. It was a perfect match: my topic was already well-aligned with the EUROfusion fusion research roadmap, and the ERG will allow me to dive much deeper into the subject, reproduce existing experiments accurately and move to important predictions for future devices from there.”
What do ERG grants enable you to do?
“They give you time to focus. As an early-career researcher you work on temporary contracts, so sometimes you need to think about what next step to take. The ERG lets me concentrate on research and delve deeper than I could otherwise. I hope to further train my research skills and make practical contributions from my project this way!”
What are the steps you are most looking forward to?
“There are many steps in my proposal, but what I really look forward to is testing the flux pumping model on data from IPP’s tokamak ASDEX Upgrade. Then I hope to expand the model with new physical extensions and calibrate it. In the end I want to test whether the model fits the data from the larger JET tokamak at UKAEA, which is the bridge towards future machines. Meanwhile, we will assist the IPP theoretical team to develop a faster, simplified surrogate model that can predict the flux pumping process more efficiently. If our results on these two devices match the data, that would let us advise ITER and DEMO on how they can achieve this self-calming effect as well.”
Finally, do you have any advice for future applicants to an ERG / EEG?
“First of all, going for an ERG or similar grant is always worthwhile because it prompts you to create a convincing vision of where your research should go. My advice is to develop a clear understanding of your topic and know how it fits into the larger research Programme. Then if you also know the risks of your approach, you are ready to talk to a panel of experts!”