-
UKAEA-CCFE-PR(23)1872023
Solution reconstruction from limited number of measurements is useful in many areas of heat transfer applications. Unlike the standard problems, such reconstruction problems are ill-posed; thus, the non-uniqueness of solution and inherent instability severely complicates the modelling process. Consequently, more conventional inverse analysis method…
-
UKAEA-CCFE-PR(23)1862023
In recent years, physics-informed neural networks (PINN) have been used to solve stiff-PDEs mostly in the 1D and 2D spatial domain. PINNs still experience issues solving 3D problems, especially, problems with conflicting boundary conditions at adjacent edges and corners. These problems have discontinuous solutions at edges and corners that are di…
-
UKAEA-CCFE-PR(23)1852023
Piping systems that transport coolant and breeding fluid are naturally an essential part of the support system of the nuclear fusion power plants. Following a campaign of operations, the reactor is required to be shut down and maintained entirely. Pipes connected to the reactor components are to be cut, re-welded or re-joined, and inspected non-des…
-
UKAEA-STEP-PR(23)162023
During development of the UKAEA’S Spherical Tokamak for Energy Production (STEP), assessment of manufacturing strategies for the inboard shield identified several gaps in knowledge. Limits arose from the modularization of this component, geometric constraints of tungsten ceramic forming, joining with low-activation interlayers and dissimilar j…
-
UKAEA-CCFE-PR(23)1302023
A Toroidal Alfven eigenmode (TAE) has been observed to be driven by alpha particles in a JET deuterium-tritium internal transport barrier plasma. The observation occurred 50ms after the removal of neutral beam heating (NBI). The mode is observed on magnetics, soft-xray, interferometry and reflectometry measurements. We present detailed stability…
-
UKAEA-CCFE-PR(23)1252023
In JET deuterium-tritium (D-T) plasmas, the fusion power is produced through thermonuclear reactions and reactions between thermal ions and fast particles generated by neutral beam injection (NBI) heating or accelerated by electromagnetic wave heating in the ion cyclotron range of frequencies (ICRF). To complement the experiments with 50/50 D/T …
-
UKAEA-STEP-PR(23)092023
While substantial research effort has been made recently in the development of computational liquid-metal magnetohydrodynamics (MHD) solvers, this has typically been confined to closed-source and commercial codes. This work aimed to investigate some open-source alternatives. Two OpenFOAM-based MHD solvers, mhdFoam and epotFoam, were found to sho…
-
UKAEA-CCFE-PR(23)1312022
We derive a simple analytical line integral expression for the relaxation volume tensor of an arbitrary interconnected dislocation network. This quantity determines the magnitude of dislocation contribution to the dimensional changes and volumetric swelling of a material, and highlights the fundamental dual role of dislocations as sources of intern…
-
UKAEA-CCFE-PR(23)1322023
First quantitative analysis of the detachment processes in the MAST Upgrade Super-X divertor show an unprecedented impact of plasma-molecular interactions involving molecular ions (likely $D_2^+$), resulting in strong ion sinks, leading to a reduction of ion target flux. This starts to occur as the ionisation source detaches from the target, lea…
-
UKAEA-CCFE-PR(23)1332022
Hard-facing alloys in nuclear applications must remain resistant to deformation and wear, whilst also minimising transmutation to problematic elements during service. To this end, the Fe-based alloy RR2450 has been developed to potentially replace Co-based hard-facing alloys. RR2450 is a complex multi-phase stainless steel alloy showing an unusuall…
Showing 351 - 360 of 2527 UKAEA Paper Results