Modular High-Field Superconducting Magnets with Demountable Joints for Fusion Energy Applications

Background to the PhD Research Project::
Modular magnets with demountable superconducting joints will be required for commercialisation of fusion energy. They will operate at cryogenic temperatures in high magnetic fields. In this project, the PhD student will design, develop and test new demountable superconducting joints made using both traditional low temperature and high temperature superconductors. These joints must meet the requirements: low-cost, low-loss, thermally, electrically and mechanically stable, and remote-handling ready. Staff with expertise and facilities in Durham (Superconductivity Group) and CCFE (STEP and RACE) will collaborate in the design and fabrication of these joints. Testing at high currents will be in high-field cryogenic facilities in Durham.
At the beginning of the 21st century, the ITER (International Thermonuclear Experimental Reactor) Tokamak that is being built in Cadarache in France is one of the most exciting scientific projects (http://www.iter.org/). It will produce 500 MW which is about ten times the power needed to run the machine. Superconductivity is the enabling technology for this project since without it, the magnets that hold the plasma would either melt or consume more energy than the tokamak produces. Approximately one third of the cost of ITER comes from the superconducting magnets which use low temperature superconductors.
After ITER, we expect new tokamaks to be built across the world that will help enable commercial fusion energy (eg DEMO - Demonstration Power Plant - and STEP - Spherical Tokamak for Electricity Production). Unfortunately the ITER superconducting magnets will not be suitable for commercialisation of fusion energy because they are not modular or demountable. If one of the TF coils at ITER is damaged, it will take at least one year to replace it. Furthermore in commercial tokamaks, modular magnets and joints will need replacing using remote handling because the levels of activation will make direct human entry impossible. CCFE have world-class expertise at RACE, including more than 20 years handling remote operations for JET. This PhD will bring together the expertise to develop next generation demountable superconducting joints for fusion energy applications.
PhD Research Project and Supervision :
The PhD research project will be experimental. It will include a collaboration between Durham University and The Culham Centre for Fusion Energy (CCFE) designing, fabricating and measuring joints for new demountable magnets. The student will focus on developing novel joint designs, considering both traditional low- and high-temperature superconductors. The timescale for first-plasma at ITER (2025) offers a wonderful opportunity for early career Physicists to help pioneer new demountable magnet designs using low- and high-temperature superconductors. They will be expected to network with scientists throughout the world working on fusion.

Identifying a sustainable energy supply is one of the biggest challenges facing humanity. Fusion energy has great potential to make a major contribution to the baseload supply - it produces no greenhouse gases, has abundant fuel and limited waste. Furthermore, the UK is amongst the world leaders in the endeavour to commercialise fusion, with a rapidly growing fusion technology and physics programme undertaken at UKAEA within the Culham Centre for Fusion Energy (CCFE). With the construction of ITER - the 15Bn Euro international fusion energy research facility - expected to be completed in the middle of the 2020's, we are taking a huge step towards fusion power. ITER is designed to address all the science and many of the technology issues required to inform the design of the first demonstration reactors, called DEMO. It is also providing a vehicle to upskill industry through the multi-million pound high-tech contracts it places, including in the UK.
ITER embodies the magnetic confinement approach to fusion (MCF). An alternative approach is inertial fusion energy (IFE), where small pellets of fuel are compressed and heated to fusion conditions by an intense driver, typically high-power lasers. While ignition was anticipated on the world's most advanced laser fusion facility, NIF (US), it did not happen; the research effort is now focused on understanding why not and the consequences for IFE, as well as alternative IFE schemes to that employed on NIF.

Our CDT is designed to ensure that the UK is well positioned to exploit ITER and next generation laser facilities to maximise their benefit to the UK and indeed international fusion effort. There are a number of beneficiaries to our training programme: (1) CCFE and the national fusion programme will benefit by employing our trained students who will be well- equipped to play leading roles in the international exploitation of ITER and DEMO design; (2) industry will be able to recruit our students, providing companies with fusion experience as part of the evolution necessary to prepare to build the first demonstration power plants; (3) Government will benefit from a cadre of fusion experts to advise on its role in the international fusion programme, as well as to deliver that programme; (4) the UK requires laser plasma physicists to understand why NIF has not achieved ignition and identify a pathway to inertial fusion energy.

As well as these core fusion impacts, there are impacts in related disciplines. (1) Some of our students will be trained in low temperature plasmas, which also have technological applications in a wide range of sectors including advanced manufacturing and spacecraft/satellite propulsion; (2) our training in materials science has close synergies with the advances in the fission programme and so has impacts there; (3) AWE require expertise in materials science and high energy density plasma physics as part of the national security and non-proliferation strategy; (4) the students we train in socio-economic aspects of fusion will be in a position to help guide policy across a range of areas that fusion science and technology touches; (5) those students involved in inertial fusion will be equipped to advance basic science understanding across a range of applications involving extreme states of matter, such as laboratory astrophysics and equations of state at extreme pressures, positioning the UK to win time on the emerging next generation of international laser facilities; (6) our training in advanced instrumentation and control impacts many sectors in industry as well as academia (eg astrophysics); (7) finally, high performance computing underpins much of our plasma and materials science, and our students' skills in advanced software are valued by many companies in sectors such as nuclear, fluid dynamics and finance.