Physical Simulation to help nuclear fusion

After a first success, the CEA & OPTIS extend their collaboration on the simulation of infrared images for fusion reactors

September 19th, 2017 | Customer Focus



Since 2010,  OPTIS and CEA have been working together on the simulation of infrared images. The aim of their collaboration is to become capable of measuring the temperature of the walls of experimental fusion reactors such as ITER, using simulation. Thanks to SPEOS, OPTIS’ spectral simulation software (UV, infrared and visible simulation), CEA can simulate and measure the temperature of the walls of fusion machines by telling the difference between the proper temperature of the walls the temperature resulting from the reflection of the infrared radiation on the wall’s materials.

« Given the highly reflective environment of the nuclear fusion machines’ tungsten walls, the interpretation of temperature measurement by infrared (IT) thermography is difficult. As René Magritte said in his famous painting «The treachery of Images», a picture is not the reality; the bright colors of an IR image are not necessarily associated with a real hot spot, but may be the result of reflections, »

says Marie-Hélène AUMENIER, Doctor at the Institute of Research on Fusion by Magnetic Containment (IRFM), CEA.

« Infrared (IR) monitoring is an essential safety tool for the machine. The integrity and correct operation of the machine depend on the interpretation of the IR measurements. Simulation is also a complementary tool to model the transport of photons in the environment and thus to differentiate reflection zones from real hot spots.» She pursues: «After having tested several solutions, it is the power of the SPEOS software which led us to choose OPTIS».


Following this first success, CEA decided to continue its collaboration with OPTIS to meet new challenges.


The CEA has chosen to use the OPTIS Virtual BSDF Bench (VBB) to define precisely the materials to be used for tokamak projects like ITER, and to optimize them. This virtual laboratory for measuring materials makes it possible to simulate the use of materials under realistic conditions of use. It provides the CEA with precise and informative images, modeling complex physical phenomena involved in the interactions of photons with matter. CEA can thus carry out a virtual control of the quality of the materials and anticipate the influence of their aging on the reactors, in particular, the degradation of their surface state and the consequences on the interpretation of the infrared measurement. This tool contributes to a better control of the performance of IR measurements, which is essential to optimize the operation of future reactors while ensuring the safety of their operation.


At the same time, the IRFM teams at the CEA center in Cadarache can now more finely model the plasma radiation, study the polarization phenomena and their possible impacts on the simulation results. SPEOS allows them to review and analyze the results as a function of the polarization properties of this plasma. This advance is a great first, made possible by the use of physically realistic numerical simulation.

"The CEA will compare these simulations with the experimental results obtained in its WEST tokamak,"

added Marie-Hélène AUMEUNIER.


These simulations are very demanding regarding computation time: the CEA has therefore opted for OPTIS HPC, which guarantees a higher calculation efficiency.

"Thanks to OPTIS HPC, we can reduce our simulation time from one day to less than one hour, and thus significantly increase the number of simulations carried out on a yearly basis,"

explains Marie-Hélène AUMEUNIER.


"Another significant advantage of the SPEOS software is that it is possible to conduct all these studies in a single environment - Dassault Systèmes' Catia V5 CAD software - and the digital model of the entire thermonuclear reactor. "

Dominique Chabaud, Technical Expert in Innovation at OPTIS, concludes:

"It is with great enthusiasm that OPTIS is committed to supporting the CEA in its new projects and to providing high-performance digital design applications in the field of research."

Photo Credit: ©P.Stroppa/CEA