Y. Q. Wang H. E. Coules C. E. Truman D. J. Smith
Elastic follow-up is a mechanical boundary condition lying between constant load and constant strain control. It exists in many engineering components operating at high temperature and can result in dramatically different creep stress relaxation and strain accumulation rates in a localized region of a component. We have performed creep tests under …
Preprint PublishedM. R. Gilbert J.-Ch. Sublet
The processing code SPECTRA-PKA produces energy spectra of primary atomic recoil events (or primary knock-on atoms, PKAs) for any material composition exposed to an irradiation spectrum. Such evaluations are vital inputs for simulations aimed at understanding the evolution of damage in irradiated material, which is generated in cascade displacement…
Preprint PublishedB. Chapman R. O. Dendy S. C. Chapman K. G. McClements G. S. Yun S. G. Thatipamula M. H. Kim
Chirping observed in ion cyclotron emission (ICE) from the KSTAR tokamak at sequential proton harmonics in the range 200 to 500 MHz has recently been interpreted (B. Chapman et al., Nucl. Fusion 57, 124004 (2017)) as due to fast, sub-microsecond, evolution of the local deuterium plasma density. This density evolution changes the plasma environment …
Preprint PublishedS. E. Sharapov H. J. C. Oliver B. N. Breizman M. Fitzgerald L. Garzotti JET contributors
Alfvén Eigenmodes (AEs) are routinely seen in present-day tokamaks and stellarators with energetic particles and they represent an attractive form of MHD spectroscopy that provides valuable information on background plasma and on the energetic particles. Possible use of AEs is assessed for MHD spectroscopy of plasma with high-velocity pellet injec…
Preprint PublishedJ.D.T. Allen A. Mottura A. Breidi
Stronger and more resistant alloys are required in order to increase the performance and efficiency 11 of jet engines and gas turbines. This will eventually require planar faults engineering, or a complete 12 understanding of the effects of composition and temperature on the various planar faults that 13 arise as a result of shearing of the γ prec…
Preprint PublishedF. Lowrie M. Gorley E. Surrey B. Wynne D. Wilkes
An investigation has been carried out to verify if the strain rate sensitivity effect of 316 steel material can be measured using the small punch test method. It was found that the effect was observed during small punch testing over a displacement rate range of 0.0125 – 1.25 mm/min, with maximum load increasing as the rate increased, and the stra…
Preprint PublishedJW Connor RJ Hastie C Marchetto CM Roach
Starting from expressions in Connor et al. (1988), we derive a one-dimensional tearing equation similar to the approximate equation obtained by Hegna & Callen (1994); Nishimura et al. (1998), but for more realistic toroidal equilibria. The intention is to use this approximation to explore the role of steep H-mode pedestals, bootstrap currents a…
Preprint PublishedA. Cackett J. Lim C. Hardie P. Klups A. Bushby
Precipitation-hardened Cu-Cr-Zr will be used in heat-sink components in the Iter tokomak. After irradiation it will not be possible to test the mechanical properties of Cu-Cr-Zr using conventional, large-scale, techniques and methods requiring reduced sample sizes will have to be used. Spherical nano-indentation is one such method. In this work, Cu…
Preprint PublishedL. Horvath C.F. Maggi F.J. Casson V. Parail L. Frassinetti F. Koechl S. Saarelma M.G. Dunne K.J. Gibson JET Contributors
Recent studies have shown that on JET with the Be/W ITER-like wall (JET-ILW) in high beta discharges with high D2 gas rates the inter-ELM temperature pedestal growth is saturated half way through the ELM cycle, leading to plasmas with reduced confinement, and that the linear MHD stability of these pedestals is inconsistent with the Peeling-Ballooni…
Preprint PublishedK. Imada H. R. Wilson J. W. Connor A. Dudkovskaia P. Hill
A new drift-kinetic theory of the ion response to magnetic islands in tokamak plasmas is presented. Small islands are considered, with widths w much smaller than the plasma radius r, but comparable to the trapped ion orbit width ρ_bi. An expansion in w/r reduces the system dimensions from five down to four. In the absence of an electrostatic poten…
Preprint Published