R. McAdams A. Sparkes A. Ash I. Day D. King M. Kovari A. Shepherd I. Turner J. Zacks D. Ciric JET EFDA Contributors
In normal operation the JET neutral beam injectors have the operating gas supplied to the ion source and the neutraliser. For tritium operation the gas is supplied to both the ion source and neutraliser at a point close to the earth grid (grid gas) due to the difficulty in producing a gas line with a secondary containment and a ceramic break fo…
Preprint PublishedJ. Shimwell S. Lilley L. Morgan L. Packer M. Kovari S. Zheng J. McMillan
Beryllium (Be) is a precious resource with many high value uses, the low energy threshold (n,2n) reaction makes Be an excellent neutron multiplier for use in fusion breeder blankets. Estimates of Be requirements and available resources suggest that this could represent a major supply difficulty for solid-type blanket concepts. Reducing the quantity…
Preprint PublishedJ. Shimwell L. Morgan S. Lilley T. Eade M. Kovari S. Zheng J. McMillan
High energy neutrons produced in future fusion reactors will cause significant transmutation reactions in the breeder blanket, including the important tritium breeding reactions. The reaction rate for a given reaction type depends on the neutron spectrum and material properties. The inventory consequences fortritium production of a solid-type breed…
Preprint PublishedM. Kovari R. Kemp H. Lux P. Knight J. Morris D.J. Ward
PROCESS is a reactor systems code – it assesses the engineering and economic viability of a hypothetical fusion power station using simple models of all parts of a reactor system, from the basic plasma physics to the generation of electricity. It has has been used for many years, but details of its operation have not been previously published. Th…
PublishedM. Kovari R. Clarke T. Shephard
We reconsider an old idea: a three-stage compound cryopump for use in fusion reactors such as DEMO. The helium “ash” is adsorbed on a 4.5 K charcoal-coated surface, while deuterium and tritium are adsorbed at 15-22 K on a second charcoal-coated surface. The helium is released by raising the first surface to ~30 K. In a separate regeneration ste…
PublishedM. Kovari C. Harrington I. Jenkins C. Kiely
If fusion power reactors are to be feasible, it will still be necessary to convert the energy of the nuclear reaction into usable form. The heat produced will be removed from the reactor core by a primary coolant, which might be water, helium, molten lithium-lead, molten lithium-containing salt, or CO 2 . The heat could then be transferred to a con…
PublishedG. Fishpool J. Canik G. Cunningham J. Harrison I. Katramados A. Kirk M. Kovari H. Meyer R. Scannell The Mast-Upgrade Team
A potentially important feature in a divertor design for a high-power tokamak is an extended and expanded divertor leg. The upgrade to MAST will allow a wide range of such divertor leg geometries to be produced, and hence will allow the roles of greatly increased connection length and flux expansion to be experimentally tested. This will include te…
PublishedM. Kovari B. Crowley S. J. Cox
Measurements have been made of the emittance plot of a partly neutralized positive ion beamlet, using a slit, a polymer target, and an infrared camera. This thermographic approach is intrinsically linear and absolute since the properties of the target are known and approximately independent of temperature. It is sufficiently sensitive that only one…
PublishedR. S. Hemsworth H. P. L. De Esch M. Kovari L. Svensson F. Villecroze
The development of the Single Aperture. Single Gap 1 MV accelerator (SINGAP) is being carried out on the 1 MV test bed at the DRFC, CEA Cadarache, France. This paper reports on the latest performance achieved with the prototype, "ITER-like" accelerator, 730 keV, 120 A/m 2 D", and of on-going measurements of the beam "halo" fraction, »10%. It revie…
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