Technology and materials

Selected research topics

Here you can find out about a small selection of the many technology and materials topics which either are currently being researched or have funding available for future work.

High heat flux components

3D vapour graphThis study involves the assessment of water-cooled, finned heat exchangers known as hypervapotrons. These have been developed to cope with the high heat fluxes present in experimental fusion devices and ancillary systems. Typically, these can sustain power densities of up to 20-30 megawatts/m2 in steady-state, using water at flow velocities < 10 m/s and operating pressures < 10 bar.

The primary objective is to use Computational Fluid Dynamics to predict the distribution of convective and boiling heat transfer within the hypervapotron geometry. If successful, the model will be used to optimise the geometry with a view to designing a 'record-breaking' high heat flux element for fusion applications.

Health monitoring of neutral beam lines

Health MonitoringA PhD has been set up in collaboration with Loughborough University to study the potential benefits of a health monitoring system on fusion systems such as the JET neutral beam system.

Reliability of fusion systems is set to become of paramount importance in the immediate and more distant future. In order for a complex machine such as ITER to operate successfully, many systems consisting of many thousands of components need to operate reliably.

Health monitoring systems analyse data gathered from many sources. By cleverly integrating the data obtained, information can be extracted on the state of the plant. In this way the health monitoring system can increase reliability by assessing the condition of systems. It can even be used to predict failures.

The aim of this study is to implement such a system on the JET neutral beam as a test case. If successful, such a system could be implemented on machines like ITER and future fusion power stations.

High heat flux materials

High Heat Flux MaterialsThis project involves fatigue testing of materials and joint types that may be relevant to high heat flux applications in a fusion power plant (for example, the divertor). Test data will be produced and analytical validation will be carried out to justify the use of the mechanical fatigue testing as opposed to thermal fatigue as would be experienced in a reactor.

The ultimate goal is to gain a better understanding of fatigue performance of tungsten/steel joints so that more accurate lifetime predictions can be made.

Metrology research

Artefacts being measured by laser lineInside JET, over 2,000 protective tiles clad the walls of the toroidal chamber and protect the machine from the energy generated during fusion research. Each tile must be installed to its designed position to be effective – this requires precision better than the width of a human hair.

Collaborative work between JET and University College London has been assessing technologies capable of performing remote, non-contact dimensional measurement inside JET during a shutdown period. The work has created a number of world-class measurement test artefacts to trial equipment, along with procedures to evaluate the collected data.

Initial results have demonstrated that the choice of measurement technology can significantly influence the final data produced particularly for fine detail such as corners and edges. Ongoing work is focused on explaining the causes of the effects seen and how they can be identified for non-contact surface measurement to be a usable tool for JET.

Global helium resources project

Helium ProjectHelium will be needed in many areas of ITER – such as cryopumping, magnets, pellet fuelling. Looking towards DEMO it was realised that fusion's helium consumption, if scaled up from JET or ITER, might become unsustainable. Commercial helium is a by-product of natural gas production.

In 2005, a three-way collaborative PhD project was set up between CCFE, the Judge Business School at the University of Cambridge and BOC Ltd., a major industrial gases company. Student Zhiming Cai built a System Dynamics model of the global helium market, examining in detail with the input of experts, the inter-relationships between supply and demand, investment, and reserves.

We are not running low in helium soon but, if commercial fusion is going to start later this century, then helium demand reduction strategies need to be put in place now so that eventually fusion becomes self-sufficient in helium, for example by extracting the gas from air as part of industrial cryogenic air separation.

Contact us for details on any of the above topics.