Construction of a unique testing machine for fusion components is underway at UKAEA.
The machine, known as CHIMERA (or Combined Heating and Magnetic Research Apparatus), will be located at UKAEA’s new Fusion Technology Facility in South Yorkshire, UK.
When it opens, CHIMERA will be the only device in the world able to subject critical fusion component prototypes to the combination of high heat flux with static and pulsed magnetic fields within a vacuum or inert atmosphere – conditions that will be faced in large fusion devices such as ITER, and in future commercial plants.
Key fusion in-vessel components like the blanket, divertor and diagnostic modules are expected to be tested. Optical Digital Image Correlation and laser metrology will be used to map 3D surface deformations and damage due to the harsh testing environment. In addition to providing invaluable test results, these and other techniques will be used to generate and synchronise component digital twins – predictive models and simulations that will be crucial to the design and qualification of future fusion power plants. This ‘virtual qualification’ is a key strand of CHIMERA’s capability and will enable virtual testing of components under conditions that cannot be recreated in an experiment.
Damon Johnstone, UKAEA’s Head of Operations, Fusion Technology Business Unit and Head of the Fusion Technology Facility, said:
“CHIMERA is a unique world-first facility in which we will be able to simulate the extreme conditions found within a fusion power plant, but without any nuclear reactions taking place.
“This will enable a step change in our ability to verify and test components for all UK and international fusion research programmes. It therefore represents a hugely important national capability, enabling industry in the UK and internationally to design, and eventually qualify, components for future commercial fusion power plants.”
Key technical specifications
| Component size | Up to 1.7m x 0.5m x 0.9m |
| Testing chamber | Vacuum or inert gas |
| Water cooling | Inlet 150°C, 1.5MPa, or Inlet 200°C– 385°C, 650 litres/min, 15.5MPa |
| Surface heating | 0.5MW/m2 over ~0.8m2
(1MW/m2 in a later phase) |
| Simulated volumetric heating | Power up to 100kW (700kW in a later phase) |
| Static magnetic field | 4 Tesla central field |
| Magnetic impulse simulating plasma disruption | dB/dt ~ 12 T/s |
| Static magnet (horizontal field) | Split-pair superconducting magnet with NbTi coils in liquid Helium baths |
| Ramp-up/down time | ~ 8 hours |
| Pulsed magnet (vertical field) | Water cooled copper conductor |
Diagnostics
- Integrated data acquisition system enabling thorough diagnosis of performance and abundant engineering data for high-fidelity model validation
- Capacity for up to 200 channels of onboard mock-up instrumentation (analogue or digital) – temperature, strain, potential probes, hall probes, etc
- High frame rate in-vessel viewing camera
- Mock-up capacitive position sensors
- Mock-up 6 degree of freedom force and torque measurement
- Digital image correlation (DIC) at component scale
To find out more or to express an interest in using CHIMERA, go to: https://ccfe.ukaea.uk/technology/fusion-technology/chimera/ or contact UKAEA Business Development Manager, John Steele: info@chimera.ukaea.uk.
