Measurements in Nuclear Fusion Reactors

Nuclear fusion has the potential to provide clean, safe energy for the benefit of all mankind in civilization-changing levels of abundance. It evokes dreams of industrialization without compromise, and of humanity unleashed from its limits. After 6 decades of research, the challenges standing in the way of commercialized fusion have been steadily chipped away to the point where there is no one single dealbreaker. Instead, we are left with a handful of smaller engineering problem to solve. 

One such challenge is the need to take measurements inside of a fusion reactor, both for scientific discovery and for simple operational requirements. The matter in the core of a fusion reactor has conditions so extreme, they literally do not exist anywhere else in the known universe. The core takes the form of a fully ionized plasma, at least 10x hotter than the core of our sun, contained in a twisted, tangled knot of turbulent magnetic fields. The armor walls of future fusion power plants, where these diagnostics devices will be installed, will be bathed in high energy neutrons and x-rays, bombarded with high energy plasmas, and will have coolant temperatures of 800C. 

We will discuss some of the reactor relevant diagnostic systems envisioned for the otherworldly conditions inside a future fusion power plant. Core density and temperature may be measured by interferometry and Thomson scattering. The plasma bombarding the armor walls may be measured using Langmuir probes. The health (i.e. the remaining uneroded thickness) of the armor walls can be measured using Micro-Electro-Mechanical Systems – which are micron-sized devices built using semiconductor fabrication processes. These innovative diagnostics will be critical to both advancing our scientific understanding of fusion and ensuring the safe, reliable operation of future reactors.

Speaker

Cedric K Tsui Ph.D., MASc, B.ScE

Dr. Cedric K Tsui is a nuclear fusion researcher specializing in plasma-material interactions and boundary plasma physics. He has contributed to the field of plasma turbulence, plasma convection driven by electric field drifts, plasma flows in advanced magnetic geometries, and on Langmuir probes. Cedric has worked in Canada, Switzerland, and the United States with the University of Toronto, University of California San Diego, and now for Sandia National Laboratories.    

Cedric is deeply optimist and enthusiastic about imagining about and building a brighter future.