Seppo Sipilä

I'm a researcher in the field of fusion plasma physics and an educator in the field of conventional nuclear reactor physics. My research combines physics, engineering and scientific computing, and I'm also involved in dissemination of related information to the general public as well as professionals.

I have extensive experience spanning more than 35 years in numerical studies of charged-particle orbits in magnetic confinement fusion devices. The Monte Carlo orbit-following code ASCOT originated as my licentiate's thesis work in the early 1990s, and has since been further developed by a steadily growing team of researchers into a versatile simulation tool that is currently used in tokamak and stellarator research around the world. Over the years I have set up and conducted ASCOT simulation studies of, e.g., radiofrequency heating, neutral beam injection, fusion alpha particle transport, wall heat loads and diagnostics signals in front-row experimental fusion devices such as JET, DIII-D, ITER, ASDEX Upgrade and EAST.

The topic highest on my research agenda in recent years is ion cyclotron resonance heating (ICRH) in tokamaks. This is one of the main methods of auxiliary plasma heating that is required for achieving fusion-relevant conditions in magnetic plasma confinement. As ICRH produces a hot tail distribution of fast ions that can cause damage to plasma-facing wall components at concentrated heat load hot spots, ASCOT's capability of modelling the ICRH tail distribution formation and evaluating the losses of energetic ions to the plasma chamber wall in realistic 3D geometry is of great international interest in the field of magnetic confinement fusion, not only for explaining observed results but also for predicting what to expect in future devices that are presently on the drawing board, like DEMO, or under construction like ITER. All this keeps me busy with code development, setting up and conducting simulations and analysing the results that are published in international fusion science periodicals and conference proceedings.

As a teacher, I give lectures at Master's level in nuclear reactor physics since the early 2000s. With the steadily growing global energy demand and the need to break away from fossil fuels while keeping up a steady and reliable baseload capacity, the renewed interest in nuclear power has steadily increased the number of students attending my lectures from about 30 (in 2020) to more than 60 (2025). I have also participated in the Finnish translation of several multimedia projects and brochures on fusion research aimed at the general public, and I'm a member of the workgroup editing the revised and complemented multi-language nuclear technology glossary of the Finnish Nuclear Society.

Teaching

PHYS-E0460 Introduction to Nuclear Reactor Physics

Keywords

Fusion, fission, plasma physics, numerical modelling, fast ions, plasma-facing component heat loads, nuclear reactor physics

Publications and contributions

See Publications and artistic outputs or ORCID / Google Scholar.