World – Fusion Group

On the performance of JET hybrid plasmas, our latest contribution published in Nuclear Fusion

September 18, 2018September 19, 2018

The Joint European Torus (JET) – Courtesy of EUROfusion

The paper entitled “Modelling of JET hybrid plasmas with emphasis on performance of combined ICRF and NBI heating” has been published by Nuclear Fusion. It advances our understanding of the optimisation of fusion performance of the recent Joint European Torus (JET) hybrid plasmas. The hybrid scenario is an advanced regime of tokamak plasma operation expected to be applied in ITER. It is characterized by a low plasma current I_p which allows operation at a high normalised beta as well as a safety factor at the plasma centre greater than 1 which is beneficial from the plasma stability point of view.

The paper focuses on the impact of neutral beam injection (NBI) and specially ion cyclotron resonance frequency (ICRF) heating on the neutron production rate. The main scheme studied is minority hydrogen (H) in a deuterium (D) plasma with D beams. The modelling takes into account the synergy between ICRF and NBI heating through the second harmonic cyclotron resonance of D beam ions which allows us to assess its impact on the neutron rate R_NT. Apart from the D scenario, the deuterium-tritium (DT) scenario is also assessed through an extrapolation of D high-performance hybrid discharges. These results are relevant for the forthcoming DTE2 campaign at JET where one of the goals is to achieve the highest possible fusion performance for a duration of more than 5 s.

Evidence of generation of non-inductive toroidal plasma current above density limit

August 20, 2018August 21, 2018

One of the key requirements to achieve steady-state power production in a fusion reactor based on the so-called tokamak configuration is to generate non-inductive toroidal plasma current in an efficient way. A recent paper published in Physical Review Letters entitled “Observation of Efficient Lower Hybrid Current Drive at High Density in Diverted Plasmas on the Alcator C-Mod Tokamak” reports on the use of lower hybrid current drive (LHCD) as an efficient mean to obtain non-inductive plasma current at high plasma densities in a diverted tokamak configuration such as Alcator C-Mod.

New cloud-based computing platform for fusion research

August 17, 2018

Since June Culham Centre for Fusion Energy (CCFE) provides a new facility to fusion scientists, named the CUMULUS Modular Data Centre. The centre contains a new cloud-based computing platform that promises to process scientific data quicker, cheaper and more accurately than ever before.

Scientific computing is an essential technology for assimilating and understanding the large quantities of data that are now commonplace in the fusion community, as well as carrying out complex predictive simulations of tokamak plasmas. To give an idea of where we are heading, the next-generation fusion experiment ITER will generate 2 petabytes of raw data each day (2,000 trillion bytes), more than JET has produced in its entire 34-year history!

Wendelstein 7-X achieves a stellarator world record

July 13, 2018July 13, 2018

Inside view the plasma vessel with graphite tile cladding. Photo: IPP

In the past experimentation round, Wendelstein 7-X achieved the stellarators’ world record for the fusion product as a result of reaching higher temperatures and densities of the plasma as well as longer pulses. Wendelstein 7-X attained a fusion product of 6·10²⁶ degrees x second per cubic metre which is the world’s stellarator record and gives first confirmation that the optimisation carried out for its design has been successful.

Spain and Croatia push the candidature of Granada for IFMIF-DONES

June 22, 2018June 27, 2018

Pedro Duque and Blazenka Divjak after signing the agreement on IFMIF-DONES. Photo: CIEMAT news.

Science and Research Ministers from Spain and Croatia, Pedro Duque and Blazenka Divjak, have signed a cooperation agreement pushing the candidature of Granada (Spain) for IFMIF-DONES facility.

Spain and Croatia presented initially independent candidatures but they joined their efforts in order to present a common European candidature. IFMIF-DONES aims to study the extreme conditions of fusion materials under energy production and particularly research on irradiation for DEMO operation. The estimated budget for the construction is between 400 and 600 million euros and the construction will take 10 years and it will be operating at least 20 years.

Barcelona Energy Days – The Energy Transition

June 19, 2018June 20, 2018

The European Union leads the clean-energy transition, aiming to reduce its greenhouse-gas emissions in 2050 by 80-95% from 1990 levels, which means almost decarbonising its energy system. The strategies for this transition were discussed today at the Energy Transition Conference in Barcelona organized jointly by the local UPC Barcelona-Tech University, Fusion for Energy, the Government of Catalonia and the municipalities of Barcelona and Sant Adrià de Besòs.