M. K. Lilley S. E. Sharapov
A discrete spectrum of compressional Alfvén eigenmodes and ion-ion hybrid eigenmodes is found to exist above the tritium ion cyclotron frequency in the deuterium-tritium D-T plasma of a spherical tokamak power plant STPP [H. R. Wilson and et al. , 19th IAEA Fusion Energy Conference IAEA, Lyon, France, (2002), No. FT/1-4]. An equilibrium magnetic w…
PublishedA. Kirk B. Koch R. Scannell H. R. Wilson G. Counsell J. Dowling A. Herrmann
Edge-localized modes (ELMs) are repetitive instabilities that occur in the outer region of tokamak plasmas. This Letter provides new information on and the implications of the evolution of the filament structures observed during ELMs in the MAST tokamak. The filaments exist for the time over which particles are being released into the scrape off la…
PublishedI.T. Chapman S. Saarelma T.C. Hender S.E. Sharapov G.T.A. Huysmans A.B. Mikhailovskii H. Meyer A. Kirk H.R. Wilson
Present day tokamaks are capable of generating toroidal flows approaching the ion sound speed. Such toroidal rotation is known to have a stabilising effect on resistive wall modes[1]. Here the effects of plasma rotation and diamagnetic drifts on the n = 1 internal kink mode and high n ballooning modes are presented with specific comparison to exper…
PublishedA. J. Webster D. J. Szwer H. R. Wilson
Modern tokamaks can produce transport barriers TBs—localized regions with an increased energy confinement. Previous studies have been unable to examine the stability of internal TBs to radially extended short-wavelength magnetohydrodynamic instabilities “ballooning modes”, for the usual case with a sheared plasma flow and a magnetic shear tha…
PublishedK. G. McClements
A full orbit code is used to compute collisionless losses of fusion particles from three proposed burning plasma tokamaks: the International Tokamak Experimental Reactor ITER; a spherical tokamak power plant (STPP) [T. C. Hender, A. Bond, J. Edwards, P. J. Karditsas, K. G. McClements, J. Mustoe, D. V. Sherwood, G. M. Voss, and H. R. Wilson, Fusion …
PublishedP. B. Snyder H. R. Wilson X. Q. Xu
Nonlinear three-dimensional electromagnetic simulations are employed to study the dynamics of edge localized modes (ELMs) driven by intermediate wavelength peeling-ballooning modes. It is found that the early behavior of the modes is similar to expectations from linear, ideal peeling-ballooning mode theory, with the modes growing linearly at a frac…
PublishedRJH Pearce AC Bell D Brennan H Boyer J Bruce T Budd PR Butcher N Davies T Edlington R Felton J Harling T Hartrampf M Hitchin S Hotchin TTC Jones R King G Lawrence R Lobel P Morgan SR Shaw M Stamp E Surrey D Wilson L Worth K Zastrow
‘Trace Tritium Experiments’ (TTE) were successfully performed on JET in 2003. The Campaign marked the first use of tritium in JET plasmas since the Deuterium- Tritium Experiment (DTE1) Campaign in 1997, and was the first use of tritium in experiments under the EFDA organisation with the UKAEA as JET Operator. The safety and regulatory preparati…
PublishedThawatchai Onjun Arnold H. Kritz Glenn Bateman Vassili Parail Howard Wilson et al.
Simulations of three Joint European Torus [P. H. Rebut et al., Nucl. Fusion 25, 1011 (1985)] type I ELMy high-confinement discharges in a power scan are carried out using the JETTO integrated modeling code [M. Erba et al., Plasma Phys. Controlled Fusion 39, 261 (1997)] with predictive core and pedestal models, which include the effect of edge local…
PublishedH.R.Wilson
Tearing modes often limit the performance of tokamak plasmas, because the magnetic islands which they generate lead to a loss of confinement, or even a disruption. A particularly dangerous instability is the neoclassical tearing mode, which can grow to a large amplitude because of the amplification effect that the bootstrap current has on an initia…
PublishedA. Kirk H. R.Wilson G. F. Counsell R. Akers E. Arends S. C. Cowley J. Dowling B. Lloyd M. Price M.Walsh Mast Team
This Letter provides information on the spatial and temporal structure of periodic eruptions observed in magnetically confined laboratory fusion plasmas, called edge-localized modes (ELMs), and highlights similarities with solar eruptions. Taken together, the observations presented in this Letter provide strong evidence for ELMs being associated wi…
Published