J. P. Martin-Collar B. F. McMillan S. Saarelma A. Bottino
We perform a study of system-scale to gyro-radius scale electromagnetic modes in a pedestal-like equilibrium using a gyrokinetic code ORB5, and compare to the results of a local gyrokinetic code, GS2, and an MHD energy principle code, MISHKA. In the relevant large-system, short wavelength regime, good agreement between the gyrokinetic codes is foun…
Preprint PublishedM. Coleman S. McIntosh
As part of our aim to develop a reactor design framework, we present here our solution for the optimisation of plasma equilibria and tokamak poloidal field systems. A 2-D, free boundary, ideal magneto-hydrodynamic plasma equilibrium solver is described. We use it within the BLUEPRINT reactor design framework to design the plasma equilibria and po…
Preprint PublishedMax Boleininger Sergei L. Dudarev
Linear elasticity theory predicts a divergent strain field at the dislocation core, resulting from the continuum approximation breaking down at the atomic scale. We introduce a minimum model that includes elastic interactions and discrete lattice periodicity, and derive a set of equations that treat the core of an edge dislocation from a solely geo…
Preprint PublishedM. Maslov A. Boboc M. Brix J. Flanagan M. Romanelli C. Price JET contributors
This work describes the behaviour of the global energy and particle confinement on JET observed in a massive database of H-mode plasmas covering almost whole lifetime of JET operations, both with carbon and metal wall. The analysis is focused on type I ELMy H-modes in stationary phases. It is shown that plasma density in that regime is determined m…
Preprint PublishedA V Chankin G Corrigan C F Maggi JET Contributors
EDGE2D-EIRENE (the ‘code’) simulations show that radial electric field, Er, in the near scrape-off layer (SOL) of tokamaks can have large variations leading to a strong local E´B shear greatly exceeding that in the core region. This was pointed out in simulations of JET plasmas with varying divertor geometry, where the magnetic conf…
Preprint PublishedC. Vincent W. McCarthy T. Golfinopoulos B. LaBombard R. Sharples J. Lovell G. Naylor S. Hall J. Harrison A.Q. Kuang
High bandwidth, high spatial resolution measurements of electron temperature, density and plasma potential are valuable for resolving turbulence in the boundary plasma of tokamaks. While conventional Langmuir probes can provide such measurements either their temporal or spatial resolution is limited: the former by the sweep rate necessary for obtai…
Preprint PublishedMatthew J. Lloyd Robert G. Abernethy Mark R. Gilbert Ian Griffiths Paul A. J. Bagot Duc Nguyen-Manh Michael P. Moody David E. J. Armstrong
High temperature, neutron irradiated single crystal tungsten, with a post irradiation composition of W-1.20±0.11at.%Re-0.11±0.05at.%Os-0.03±0.01at.%Ta was characterised using a combination of Atom Probe Tomography (APT) and Scanning Transmission Electron Microscopy (STEM). APT showed that within nanoscale clusters of Re/Os, the atomic density wa…
Preprint PublishedPui-Wai Ma S. L. Dudarev
CALANIE (CALculation of ANIsotropic Elastic energy) program evaluates an elastic interaction correction to the total energy of a localized object, for example a defect in a solid material simulated using an {it ab initio} or molecular statics approach, resulting from the use of periodic boundary conditions. The correction, computed using a fully el…
Preprint PublishedChristopher Ham Andrew Kirk Stanislas Pamela Howard Wilson
Fusion is one of very few options for sustainable, baseload power to the grid that is necessary to meet the energy needs of future generations. The tokamak is the most advanced approach to fusion and, with the construction of ITER, we are approaching power plant conditions. While commercialisation of this key technology is a main driver for tokamak…
Preprint PublishedA.J. Cackett C.D. Hardie J.J.H. Lim E. Tarleton
We analyse spherical nanoindentation of single crystal copper using two different indenter tips of radii 7.4 and 27 um. The surface deformation surrounding the indents was measured using atomic force microscopy and the elastic rotation fields under the indents were measured using electron diffraction and transmission techniques. Using the measured …
Preprint Published