PhD Defence by Raheesty Devi Nem: Probe Measurements in the X-Point Region at ASDEX Upgrade

The defence will be carried out as an online video conference.

For signing up as audience, please contact Marianne Lüttchemeier Balle: mlballe@fysik.dtu.dk

 

Supervisor

Professor Volker Naulin, DTU Physics

Co-supervisor

Dr. Thomas Eich, Max Planck Institute for Plasma Physics, Germany

Examiners

Professor Christian Theiler, Swiss Federal Institute of Technology, Lausanne, Swiss Plasma Center, Switzerland

Engineer, PhD, Martin Hron, Institute of Plasma Physics of the Czech Academy of Sciences, Czech Republic

Senior Scientist, Stefan Kragh Nielsen, DTU Physics

Chairperson

Professor Jens Juul Rasmussen, DTU Physics

Abstract

In a millennium with accelerating changes, the energy consumption is growing rapidly. To meet this demand the amount of fossil fuel burnt has led the world in an unsustainable path causing global warning.

Energy production and use make up for approximately two third of the released greenhouse gas globally. Therefore as an effort to combat climate change it is crucial to decarbonize the power sector and invest in scale-able renewable energy sources and one such candidate is fusion. Fusion has the potential to become a key source of low-carbon electricity generation for the world. The unlimited fuel reserve available, for fusion processes to take place, can meet the global energy demand for millions of years.

With all its attracting features fusion comes at the cost of complexity due to the extreme conditions required for the ions to fuse. There are very few material that can withstand these conditions and therefore, the hot ionized gas (plasma) is confined by huge electromagnets such as to avoid the plasma to come in contact with the wall of the fusion device. However, the turbulence-induced transport is inevitable and it increases the plasma-wall interactions.

This thesis focuses on fluctuations studies caused by the turbulent transport such as to get an insight of how these fluctuations may be controlled for the benefits of fusion energy. Using a filtered Poisson process model the fluctuations have been characterized and compared at different regions of a fusion device. Characterizing these fluctuation is important to develop theories and to perform simulations to predict the behaviour of the plasma better.

Lastly, the findings of the thesis sets a starting point for fluctuation study in the Xpoint region, on which limited literature is available.

Time

Fri 06 Nov 20
14:00

Organizer

DTU Fysik

Where

The PhD defence will be held online