Record turnout spotlights crucial role of JOREK code

On site attendees at this year's annual meeting © Nadia Barth /EPFL

On site attendees at this year's annual meeting © Nadia Barth /EPFL

The annual JOREK General Meeting successfully took place on EPFL campus from 12th to 16th February 2024. Hosted by the Swiss Plasma Center (SPC) for the first time, this event gathered more than 60 on-site and remote attendees across Europe, Asia and the US, marking the highest number of participants to date. 

The record number of attendees at this year's annual meeting reflects the importance and gaining popularity of the JOREK code. It stands out for its versatile and high-fidelity code capable of modeling large-scale plasma instabilities in magnetic confinement fusion devices such as tokamaks and stellarators. These devices, often likened to "cages," are designed to accommodate high-temperature fusion plasmas of up to 150 million degrees.

Impact of plasma instabilities
Large-scale plasma instabilities, however, have a tendency to break the confinement of the plasma, facilitating its escape from the cage. This can limit the achievable fusion power and may even result in a sudden loss of plasma energy in tokamaks, a phenomenon known as "disruption". Additionally, it could cause erosion and melting of plasma facing components, exert substantial electromagnetic forces on tokamak structures and generate relativistic electrons, also referred to as "runaway electrons," which can result in damage to the wall. Recognizing the broader implications, the study of plasma disruption becomes fundamental for the development of future tokamak devices such as ITER and DEMO. In addressing this crucial aspect, JOREK sets itself apart as the only existing code in Europe capable of studying these instabilities and plasma disruptions with realistic plasma geometries.

Strong involvement of SPC
SPC is a major contributor to the development of the JOREK code and its application in plasma disruption studies, with an expanding local JOREK team. Cristian Sommariva and Mengdi Kong, the local organizers of the JOREK General Meeting this year, are focusing on investigating the generation and dynamics of runaway electrons and the mitigation of plasma disruptions, respectively. Two PhD students, Lili Édes and Chizhou Wang, have recently joined the group and started to contribute to plasma disruption studies with JOREK.

The JOREK code is also deeply involved in all aspects of the European fusion energy roadmap led by the EUROfusion Consortium: from the design and the interpretation of present experiments through the Work Package Tokamak Exploitation to the explanation of complex dynamics of hot plasma (Theory Simulation Verification and Validation programs TSSV 8 and 9). In addition, the numeric and the algorithms composing the JOREK code are kept at "the state of the art" thanks to the support of the Advanced Computing Hub initiative (ACH).

The atmosphere was friendly, highly cooperative, and filled with abundant, exciting, and very interesting discussions

Cristian Sommariva, scientist at SPC

To exchange the latest advancements in JOREK activities, address open questions, and enhance collaboration within the JOREK community, the General Meeting featured oral presentations, open discussion sessions, a guided tour of SPC facilities, and a social dinner. Cristian Sommariva, scientist at SPC, describes the atmosphere during the meeting as “friendly, highly cooperative, and filled with abundant, exciting, and very interesting discussions.”

For further information, please, refer to the website of the JOREK code.