In about 10 years time, physicists will take a significant step towards commercial fusion power with the opening of the ITER experimental reactor in Cadarache, France. ITER will use magnetic fields to confine an extremely hot mixture of tritium and deuterium in a torus-shaped chamber with the aim of developing the know-how to build a commercial fusion reactor.

ITER will achieve fusion in a “pulsed mode”, with each pulse lasting hundreds of seconds. Researchers will analyse data from successive pulses and use this information to improve their experimental strategy — with the ultimate goal of sustaining fusion over much longer periods of time. This will involve the acquiring and rapidly processing vast quantities of data.

Founded in 1980 by the physicist Kevin Gell, Tessella began by supplying software for mainframe computers at the United Kingdom Atomic Energy Authority’s (UKAEA) Harwell research facility in Oxfordshire. A few years later, the firm’s scientific software specialists began work on many of the key computer systems used at the Joint European Torus (JET) experiment at the UKAEA’s nearby Culham facility. From these beginnings, Tessella now employs more than 200 technical staff in the UK, mainland Europe and the US.

Long list of ‘firsts’

JET has been the world’s leading centre for research into fusion power since it opened in 1983. The experiment has achieved a long list of ‘firsts’, including the record for the amount of energy generated by a fusion reactor. The facility has kept its pre-eminence through an ongoing programme of enhancements, and JET is now being used to study potential operating scenarios for ITER. This essential work is expected to continue over the next decade.

More than 70,000 experiments have so far been carried out at JET — with around 30 experiments (or “pulses”) being run on a typical operating day. Collecting and managing all of this data is no mean feat.

During any one pulse, a large number of physical parameters are measured using over a hundred diagnostic instruments. The data are then processed using a workflow process that turns raw scientific data into more useful information through a complex chain of software. The raw and processed data are stored, and presented to the operators ready for use in setting up the next pulse. Summary data are generated for scientists to plan the pulse programme and complex models are run to predict the plasma behaviour.

Throughout the lifetime of JET, the amount and complexity of data gathered, processed, presented and modelled has increased dramatically. An ongoing challenge for people developing its IT systems has been meeting the demands of the fusion researchers, while evolving JET’s computer systems over many generations of hardware and software.

Key roles at JET

Tessella has fulfilled many key roles as part of the team supporting JET’s evolving research programme. These includes the support and enhancement of some of the facility’s main computing platforms from the mainframes of the 1980s to the Linux clusters of today as well as successive generations of software architectures that manage the processed pulse data.

Tessella has optimized the between-pulse processing workflow on the current Linux cluster and has produced a number of data visualization and statistical analysis systems using various mathematical packages. We have also developed complex plasma behaviour models as well as PC-based data-acquisition systems for the experiment itself.

Throughout the dramatic changes required in computing architecture, software and dissemination of data, Tessella has worked hard to ensure that all processed data have remained accessible — even information dating back to the first-ever pulses back in 1983. This attention to digital archiving allows JET to achieve one of its primary aims: to provide data to physicists designing ITER and other fusion experiments of the future.

Sharing fusion data around the world

ITER researchers are located throughout the world and must be able to access and share relevant information as easily as possible. To this end Tessella has been involved in revamping the ITER technical website and intranet while migrating both to the Microsoft SharePoint platform — and ensuring that both are coupled to the ITER Document Management System (IDM).

Over the past two decades Tessella has gained a thorough understanding of what fusion scientists and engineers need to manage and present data and technical documents. This has allowed the firm to improve the search methodology and knowledge-management capabilities of the ITER technical website and intranet. In addition users are now able to update their own web pages and more advanced users are able to edit content and create richer content.

As Tessella’s project manager for fusion, I have been working directly on JET for a number of years and I believe that our success and longevity with the facility is a result of our ability to field professional software engineers and project managers who have exactly the right academic backgrounds. Today, the company has physicists, mathematicians and engineers working on both JET and ITER, which is fundamental to Tessella’s continued involvement with these projects and to our ability to support other large research projects.