High current and low q95 scenario studies for FAST in the view of ITER and DEMO

The Fusion Advanced Study Torus (FAST) has been proposed as a possible European satellite, in view of ITER and DEMO, in order to: a) explore plasma wall interaction in reactor relevant conditions b) test tools and scenarios for safe and reliable tokamak operation up to the border of stability c) address fusion plasmas with a significant population of fast particles. A new FAST scenario has been designed focusing on low-q operation, at plasma current IP=10 MA, toroidal field BT=8.5T, with a q95=2.3 that would correspond to IP=20 MA in ITER. The flat-top of the discharge can last a couple of seconds (i.e. half the diffusive resistive time and twice the energy confinement time), and is limited by the heating of the toroidal field coils. A preliminary evaluation of the end-of-pulse temperatures and of the electromagnetic forces acting on the central solenoid pack and poloidal field coils has been performed. Moreover, a VDE plasma disruption has been simulated and the maximum total vertical force applied on the vacuum vessel has been estimated

Eurofusion-DEMO Divertor - Cassette Design and Integration

The Eurofusion-DEMO design will complete the Pre Conceptual Design phase (PCD) with a PCD Gate, named G1, scheduled to take place in Q4 2020 that will focus on assessing the feasibility of the plant and its main components prior to entering into the Conceptual Design phase. In the paper first an overview is given of the Eurofusion-DEMO Divertor Assembly including design and interface description, systems and functional requirements, load specification, system classification, manufacturing procedures and cost estimate. Then critical issues are discussed and potential design solutions are proposed, e.g.: - Neutron material damage limits of the different (structural) materials present in the divertor assembly (as CuCrZr, Eurofer) and in the vacuum vessel (AISI 316 L(N)-IG); - Temperature hot spots in parts of the divertor assembly exposed to high nuclear heating and high heat radiation (from the plasma core or the separatrix) causing difficulties for active or passive cooling (e.g. cassette body structure, liner support structures, mechanical supports, divertor toroidal rails); - Arrangement and design of plasma-facing components and liner with pumping slot in the divertor cassette to enable pumping of exhaust gases from the lower port

Near term perspectives for fusion research and new contributions by the Ignitor program

The main advances made within the Ignitor program, that is aimed at investigating the physics of fusion burning plasmas near ignition, are described. In particular, the operation of the machine in the H and I regimes at the 10 MA plasma current levels has been considered and analyzed. The unique properties of the plasmas that can be generated by operating the machine with reduced parameters (lower magnetic fields and plasma currents) relative to those needed to achieve ignition are identified. A key feature of this operation is the relatively fast duty cycle that can be maintained. The Ideal Ignition Conditions, under which the density barrier due to bremsstrahlung emission in high density plasmas is removed, can be attained in this case. The plasma heating cycles are identified for which the contribution of ICRH is used both to enter the H-regime and to optimize the time needed for ignition. The on going effort to set up a test ICRH facility is described. The initial results (2 km/sec) of the high speed pellet injection system developed for Ignitor and operated at Oak Ridge are reported. The combined structural analysis and integration of the entire machine core (Load Assembly) is discussed. The adopted control system for both the machine and the plasma column has been designed and is described. The design solutions of the vertical field coils made of MgB2 and operating at 10 K have been identified and the relevant R&D program is underway. The analysis of the Caorso site and of its facility for the operation of the Ignitor with approved safety standards is completed. The relevant results are being made available for the operation of Ignitor at the Triniti site within the framework of the Italy-Russia agreement on the joint construction and operation of the Ignitor facility. A development effort concerning the advanced diagnostic systems that is being carried out for fusion burning plasma regimes is described. An initial analysis of the characteristics of a neutron source based on a system of Ignitor-like machines is reported

Repensando a história do karate contada no Brasil

Este estudo aborda diversos aspectos presentes na literatura e que moldam o pensamento presente no imaginário dos brasileiros sobre a identidade, história e filosofia do Karate-Dō¹. O objetivo deste estudo é produzir uma meta análise da literatura circulante sobre a inserção e o desenvolvimento do Karate no Brasil, abordando seus diferentes estilos. Justifica-se este estudo pelo fato de considerarmos que foi difundida no Brasil uma versão distorcida sobre a história do Karate por meio da mídia, pela tradição oral e pelo preconceito entre os praticantes de diferentes estilos. As reflexões aqui apresentadas buscam contribuir com informações para a construção de outra versão sobre esta prática em nosso país.This study approaches several aspects of literature that shape the present thinking in the Brazilians imaginaries about the Karate-Dō identity, history and philosophy. The objective of this research is to produce a meta-analysis of the spread literature approaching is different styles. This study is justified by the fact of we consider that a distortion of Karate-Dō history was diffused in Brazil, by the media, oral tradition and preconception between some Karate-Dō styles practitioners. The reflections presented here seek contribute with information for another version's construction about this practice in Brazil

Divertor of the European DEMO: Engineering and technologies for power exhaust

In a power plant scale fusion reactor, a huge amount of thermal power produced by the fusion reaction and external heating must be exhausted through the narrow area of the divertor targets. The targets must withstand the intense bombardment of the diverted particles where high heat fluxes are generated and erosion takes place on the surface. A considerable amount of volumetric nuclear heating power must also be exhausted. To cope with such an unprecedented power exhaust challenge, a highly efficient cooling capacity is required. Furthermore, the divertor must fulfill other critical functions such as nuclear shielding and channeling (and compression) of exhaust gas for pumping. Assuring the structural integrity of the neutron-irradiated (thus embrittled) components is a crucial prerequisite for a reliable operation over the lifetime. Safety, maintainability, availability, waste and costs are another points of consideration. In late 2020, the Pre-Conceptual Design activities to develop the divertor of the European demonstration fusion reactor were officially concluded. On this occasion, the baseline design and the key technology options were identified and verified by the project team (EUROfusion Work Package Divertor) based on seven years of R&D efforts and endorsed by Gate Review Panel. In this paper, an overview of the load specifications, brief descriptions of the design and the highlights of the technology R&D work are presented together with the further work still needed