Yann Cressault: thermal plasmas and electrical arcs

By Jennifer Sanders on December 4, 2015

Dr Yann Cressault is an expert in thermal plasma physics and electrical arcs, and works at the LAPLACE Laboratory in Toulouse, France.

Let’s find out a bit more about Dr Cressault, his research and what interests him outside of science.

What research projects are you and your group currently working on?

The researches of the Arc Electrique et Procédés Plasmas Thermiques (AEPPT) team at the LAPLACE laboratory are focused on thermal plasmas and electrical arcs in interaction with their environments: materials, gases, humans. Our studies are motivated by the questions close to those of the scientific community and the social-economic world. Answering these questions requires a range of diverse skills on characterization of the phenomena, experimental studies, physical analyses, and development of numerical models or tools. My researches are focused on the properties of thermal plasmas: calculation of the radiative properties, thermodynamic properties and transport coefficients in order to better understand the behaviour of the arc/plasma in industrial applications such as plasma spraying, plasma cutting, plasma welding, or in several industrial systems such as lamps or circuit breakers (high and low voltages).

What motivated you to pursue this field of research?

Photos of a plasma arc with copper electrodes

My motivation is due to the fact that my researches are strongly linked not only to industry applications but also to humans. We find electric arcs in aeronautics (arc tracking for example), metallurgy (cutting, welding, spraying), medicine (production of nanoparticles), lamps, and more. Bbehind the applications, we have so many challenges: to better understand the creation or the extinction of the arc, its behavior, its properties, the influence of the arc/plasma on the surrounding materials or gases, or the inverse: erosion of the walls, erosion of the electrodes, skin diseases, radiation emitted, and so on. Each project is a new challenge that I have to win. For some applications, such as plasma welding or plasma cutting, the goal is to improve the process. For the lamps, the goal is to improve the lighting by limiting the radiation responsible for skin diseases. There are so many industrial processes using electrical arcs or so many things to study when electrical arcs exist.

Where do you think the field is heading?

Actually, the thermal plasma community knows how to characterize the hot regions of thermal plasmas whether it is by experimental measurements, numerical modelling, or by the calculation of thermal plasma properties. In these regions, the plasma is supposed to be in thermal and chemical equilibrium. In the surrounding regions, i.e. close to the wall or close to the electrodes, there can exist departures from equilibrium due to different gradients, such as temperature, pressure, density, or electric charges. Consequently, further work on thermal plasmas properties will certainly be focused on two-temperature or multi-temperature plasmas: plasma compositions, thermodynamic properties, transport coefficients, 3D numerical modelling, experimental setups.

One from a series of images taken by Yann Cressault of Mauna Kea (sunrise), and Halakeala (sunset) in Hawaii at the GEC conference, October 2015

What interests you outside of science?

It’s a very difficult question. I have other interests such as travels, philosophy, history or photography. Through my travels I like discovering new populations, new countries, new customs and discussing with other people who have different origins. Philosophy is a way for me to think differently, history the way to understand civilizations, and photography the best way to immortalize a moment, a landscape, a face and realize how nature and life are so precious.

If you weren’t a scientist, what would you be?

When I was younger, I wanted to be an animal reporter in Africa to study very interesting and impressive animals, after that an architect, then a veterinarian and finally a doctor. Today, I could be a sailor, a politician, or a defender of nature and population.

If you were a young physicist just starting out today, what would you study?

I think I would study volcanoes, the glaciers or the stars. Humans are so small in front of these forces of nature.

Read work from Yann Cressault, with his group and collaborators

“Radiation of long and high power arcs” Y Cressault et al 2015 J. Phys. D: Appl. Phys. 48 415201

“Two-temperature thermodynamic and transport properties of SF6–Cu plasmas” Yi Wu et al 2015 J. Phys. D: Appl. Phys. 48 415205

“Thermodynamic properties and transport coefficients of high-temperature CO2 thermal plasmas mixed with C2F4” Aijun Yang et al 2015 J. Phys. D: Appl. Phys. 48 495202

This work is licensed under a Creative Commons Attribution 3.0 Unported License

Image 1: Courtesy of Yann Cressault, copyright.

Image 2: Photos of a plasma arc with copper electrodes from Y Cressault et al 2015 J. Phys. D: Appl. Phys. 48 415201, Copyright IOP Publishing Ltd 2015

Image 3: Courtesy of Yann Cressault, copyright.