Inertial confinement fusion reactor

Context

Two methods are currently being considered for producing energy by nuclear fusion:

The first is magnetic fusion, in which the plasma is confined by powerful magnetic fields within a toroidal vacuum reactor. The plasma is heated to very high temperatures (around 150 million degrees Celsius) to initiate the fusion reaction. This is the method used for the better-known ITER project and all tokamaks.
The second approach is inertial confinement fusion, used for the HiPER project. In this approach, the fuels (deuterium and tritium) are enclosed in granules a few millimeters in diameter, and compressed by powerful lasers. The plasma reached by these beams instantly reaches a very high density and temperature. The conditions for fusion reactions are then created and energy is released.

Objective

The aim of the study is to model natural convection movements within the reactor target. However, given the physical phenomena involved, it is necessary to achieve extreme levels of accuracy, which the most popular CFD methods (finite volumes) do not allow.

Simulation and results

To achieve these levels of accuracy, we use the Nek5000 calculation code, based on the spectral element method. Our results demonstrate that these methods are sufficiently accurate for nuclear fusion simulation applications.

Overall, CFD simulation for the nuclear industry has a wide range of applications, both for fusion technologies under development and for fission technologies already in service. The applications of CFD simulation to the nuclear sector are numerous, from the study of fundamental turbulence in plasma to more trivial subjects such as the cooling of various components (e.g. transformer cooling).